The DS Lite's screens were a huge improvement on the wishy-washy displays of the original DS, and the DSi's screens are even better, the additional size and marginally improved brightness making this the most comfortable DS for long-term use yet. There's no difference in terms of resolution - we're still talking 256 x 192 pixels - but colours seem ever-so-slightly richer and clarity is superb. It's a pleasure digging out old favourites like Zelda: The Phantom Hourglass or Professor Layton and the Mysterious Village just to appreciate how good they look, and the new screens certainly make the teeny-tiny graphics of Rockstar's phenomenal GTA: Chinatown Wars that little bit easier to make sense of.
There are other hardware changes under the bonnet. As always, Nintendo is cagey about the DSi's exact specification, but the old 67MHz ARM 9 and 33MHz ARM 7 CPUs have been upgraded to a newer ARM 9 or ARM 11 processor running at - it's believed - 266MHz. RAM, meanwhile, has gone up from 4 to 16MB. On top of this, the unit has 156MB of built-in flash memory.
Why such substantial upgrades for what is apparently an evolutionary product, not a DS sequel? Well, for the moment at least it's not for the expected reason; to make more advanced or graphically intensive games. Nintendo isn't launching the DSi with a range of DSi-specific games to show off the hardware, though there are plans to release DS-compatible games with additional DSi features. Instead, the impetus behind the hardware changes seems more to be about image and audio manipulation, Internet applications and the applications you'll be able to download from the all-new DSi store.
You'll find all these features upfront in the new DSi interface, which takes its look and feel directly from the Wii's GUI. The home page has a series of horizontally scrolling boxes, featuring a settings menu, the currently installed cartridge, the new DSi camera and sound apps, the DSi Shop, Download play and our old friend, Picto-Chat, along with a huge series of empty boxes sitting there ready to accept other applications at a later date.
The camera app will be most people's first port of call. It's very nicely done and targeted directly at the family audience, allowing you to switch between the built-in memory or the currently inserted SD card, then take images using either camera and save them into albums organised by calendar. Image quality is exactly what you'd expect; colours are mostly fine, but the low resolution is a limiting factor and noise is an issue in dark or even gloomy conditions. However, that's not really the point - it's unlikely that you'll use the DSi as your main digital camera, and most of us are more likely to use one built into our current choice of phone.
What is the point is fun. The camera app includes a range of 'lenses' which can be used to warp or colour faces or objects in the image, scrawl over the picture, super-impose sunglasses or a moustache, plus a selection of other effects. The clever bit is that you can apply these effects in real-time, both while you're capturing the image and once it's in the album after capture. It's quick, it's entertaining, and while it's nothing you couldn't do with a PC, appropriate software and a digital camera or Webcam, there's something so immediate about it on the DSi that you can't help playing around with it. Images stored on the SD card can, of course, be taken off the DSi and onto a PC or Mac.