Two years ago the proportion of the world's population living in cities eclipsed those living elsewhere for the first time in history. The trend has persisted, in fact it seems an unstoppable juggernaut with the ratio predicted to reach 3:1 by 2050. Of course, city-dwelling is nothing new, but cities that 20 million people may call home certainly are. As Justin McGuirk discusses in this article, the transformation presents some of the most profound design challenges of our era. The process of regeneration is relentless - you can't go far in New York or London without seeing immense construction work underway, or derelict buildings whose future is no doubt already a glint in the eye of some ambitious developer.

If you're one of the nation's 5 million BBC iPlayer users (or perhaps, for our US friends, one of 40 million Hulu users) the murky boundaries between 'using the internet' and 'watching TV' will be familiar. From enjoying shows online to - in the near future - reading news and catching up on e-mails on our plasma TVs, the magical process of 'convergence' is charging its way into the new decade. When you can sit on the bus and watch live TV with the rather spiffing TVCatchup, you know the days of bluntly differentiating between computing devices and TVs are numbered.

Technology firms hoping to catch such disruptive waves of change meet annually at the Consumer Electronics Show in Las Vegas, boasting the wares they hope will enter our homes in coming years. It's a veritable trend-seekers paradise, and one particular trend at this year's event leapt out (almost literally). 3D TVs, capable of showing the new breed of 3D films like James Cameron's Avatar in all their splendour, will eventually find their way into our living rooms. That alone is revelatory, but in parallel with the convergence stampede presents one huge floating 3D question mark for interface design.

Experiments with 3D interfaces are not new, but have begun gaining traction with the emergence of gesture-based devices, particularly multi-touch devices like the all-conquering iPhone and Microsoft's Surface. One approach I've been watching with interest is BumpTop, revealed with an eye-opening TED talk (listen to the oohs and aahs) and now available to the public.

It seems like only days ago that I was writing a post about search engines and social recommendation, and that's because it was only days ago. Since then - decades in internet time - some interesting developments have taken place.

The hype around real-time search, particularly focussed on everyone's favourite micro-blogging service, has certainly caused the major search engines to take note. The power of real-time data, most obviously encapsulated in Twitter's trending topics, seems to prove itself weekly (or, if you like, instantly).

At the core of my previous post was the inclination that, despite the hype, major search engines and services like Twitter have entirely different missions - and they know it. Both the widespread creation of real-time data, and appetite for its consumption, are relatively recent phenomena. If this information is being created, and is valuable, Google will work to index it as part of its mission to organise the world's information. Indexing tweets is one important step towards this, and... hey look they announced it. As did Bing, Microsoft's new search engine. The latter seems to have rushed out a rather confusing solution, the big G is taking its time, and I for one will be watching carefully to see how they roll this out without disrupting their archetypal search results page and carefully honed user experience.

Last week I put "W1F 0TF" into trusty ol' Google Maps and found my way to the Slug & Lettuce on Wardour Street for Chinwag Live's 'Search is Dead, Long Live Search' event. Examining some of the key challenges currently facing search engines, and what these may mean for brands, web companies (not least SEO agencies) and users in general, the lively panel discussion helped crystallise some ideas I've been pondering in recent times.

Just as the ferocious 'Browser Wars' continue to rage, the fight for search engine dominance remains in full force. In the West we are so familiar with you-know-who that the word 'Googled' is poised to become the 21st Century 'hoover' and lose its capitalisation, so we'd be forgiven for thinking the battle effectively ended some time ago. But step away from the primary colours; the story isn't so simple. First, look to the Far East where the landscape is remarkably different - Baidu holds a mountainous 69% in China, while Google has only a hilly 25% (July 2009). Second, stop thinking about search purely in terms of the 'traditional' search engines, since these now represent only one of many powerful ways to discover content, and the picture is less clear.

Not so long ago, Eleanor Rudge and I headed up to the British Museum for a conference on 'Designing for disability', organised by the Museums Association.

The aim of the day's talks was to

November's Codeo challenge (to revolutionise that old gem, Tetris, using Javascript) was undoubtedly a tough one, and really separated the cowboys from the critters. So well done to the sharp-shootin' coders who rose to the challenge.

There could only be one winner, however, and Simon Wibberley emerged victorious with his mind-bending 3-D Tetris created with Processing, a programming language designed for the electronic arts and visual design communities.

Howdy partners! The first monthly Codeo competition has drawn to a close, and boy was it a tough call for our judges. All the entrants really pulled it out the bag with our Scratch challenge - the Wild West Scratch Showdown; we'd never seen the likes.

I've been spying on my neighbours.

I've been listening in on their conversations, stealing little snapshots of their lives. Don't be too alarmed - they've also been spying on me. We're all in this game of espionage together.

No, it's not Neighbourhood Watch - it's location-aware twittering. If you've been twittering within a 5km radius of me, I might just know about the film you enjoyed on Sunday, or your thoughts on the roadworks...

OK, such voyeurism is admittedly not that interesting. Yet.

I'm fairly new to the 'mobile web', having suffered for too long with handsets that take you to a 'web portal' with news from your friendly network provider and poorly displayed text-pages (that cost a fortune to view). Thankfully Apple have helped shake up the market, and more and more people are starting to experience the mobile web in one way or another (with shiny iPhones, or any number of other newer phones that are addressing the less-than-perfect user experience of yore).

As everyone knows, the uptake of mobile phones has been an incredible modern story. The penetration is so great, people will probably think you're pretty strange if you haven't got one. Behaviour has changed for everyone - even if you don't carry one you'll find that decision affects the people who want to contact you. It's hard, as they say, to imagine how we ever lived without them....

So now that serious uptake of the mobile web has begun, will it be on a par? Will it change behaviour as dramatically?

I think the answers are "yes" and "yes" again, which is why I went on Tuesday evening to a Chinwag event about mobile search and location-based services. It was a panel discussion, chaired by some interesting people from nascent (and more established) businesses seeking to really capture a part of this new territory. These including Taptu (mobile social search), Rummble (for personalised recommendations), Plazes (a mobile social network) and The Cloud (the Europe-wide WiFi hotspot service).

A great deal was discussed through the evening, but I'll focus on a single area.... spying!

Well, almost; let's call it the 'tracking versus publishing' problem.

Attention, budding programmers!  This week, Cogapp is pleased to announce the launch of Codeo, a monthly coding competition for students in the Sussex area. Challenges will range from mini-games to programming puzzles, and a cash prize of £100 will be up for grabs for each winning entry.

Ever find yourself standing at a bus stop, starring at a poster for the latest Hollywood Blockbuster, and wondering "well, looks exciting, but what's it all about?!"? ViPR Visual Search, developed by Evolutionary Robotics, promises an answer.