By Darren Waters
Technology editor, BBC News
Visually, there is little difference between Nintendo's DS Lite and DSi
Nintendo launches its revamped handheld console - the DSi - in the UK, hoping to maintain the global success of its portable device.
With more than 100 million Nintendo DS handhelds shipped around the world, there might not seem to be much of a need to tinker with the device that has become the dominant platform in the handheld console market.
Given the current rate of sales of the machine, it would be no surprise if the DS were to overtake the PlayStation 2's global sales of 150 million to become the most popular dedicated gaming platform of all-time.
When Nintendo first launched the DS, its chunky, retro design and two-screen, touch screen approach - combined with the lack of a web browser and inability to play multimedia - baffled many observers.
Sony's sleek PlayStation Portable with its more advanced graphics hardware, UMD movie library, and connectivity with a PlayStaton 3 seemed the obvious victor in the handheld console race.
Wind the clock on four years since its launch and there is only one winner.
While the PSP has sold modestly well, the DS has steamrollered it - one key element in Nintendo's strategy to broaden the appeal of gaming. In 2008, 47% of DS sales in 2008 were made to women.
But there is a sense that the Nintendo DS is beginning to age.
Newer rivals - including more powerful mobile handsets such as the Nokia N81 and N96, as well as the Apple iPhone and iPod Touch, with more than 30 million sales - are now serious contenders.
Nintendo's answer would appear to be the DSi.
At first glance you would be hard pressed to tell the difference between the second generation DS Lite and the new machine.
The built in camera will only take pictures at 0.3 megapixel resolution
The DSi is slightly thinner, with 8% more screen size, but such external changes are generally more aesthetic than tangible.
So what else is new?
It has two built-in cameras, a SDHC card for more storage, the ability to record sound and playback AAC files, a web browser, a focus on personalisation through playing with audio and vision and a new DSi online shop, through which developers are being encouraged to "think outside the box" with new applications.
The headline changes sound impressive, but the details reveal a disappointing lack of change.
The DSi can only play back AAC, not MP3, arguably the globe's common digital audio standard.
The two cameras are only 0.3 megapixels - so pathetic indeed that it makes the iPhone's famously poor 2 megapixel camera look like a Hasselblad.
Once again, Nintendo has changed the charging cable, so if you are an original DS or DS Lite owner, you won't be able to use your existing cable as a spare.
Own worst enemy
The internal storage of the device is just 256 megabytes - and applications have to run in this paltry amount of storage.
The DSi is no longer compatible with GameBoy Advance games either.
Nintendo are caught in a dilemma of their own making.
With more than 100 million Nintendo DS handhelds already sold, the company cannot afford to turn their back on this audience and encourage developers to create games that use the DSi as the starting template.
So there is unlikely to be much change to the core experiences that games for the Nintendo DS offer.
The changes will be at the fringes - through the DSi shop, and the possibility that some first-party games will be "enhanced" for the DSi.
Nintendo's first device - the NDS - sold over 150 million units
And while the Nintendo DSi largely stands still, rival devices are adding new features all the time: from accelerometers to near HD resolutions in your pocket, GPS and the combination of gaming with mobile communications.
Nintendo, of course, has been written off before, and it would be foolish to do the same again.
The company has successfully shown that simple, addictive games prove very attractive with users, without the need for technically clever controls systems or mobile communications.
But many observers were hoping the company would have gone a little further, a little faster.