The most notable new component in the 2009 edition Mac mini is the same nVidia 9400M IGP chipset that Apple has used in its unibody MacBook line and which also features in the new iMac range. Unsurprisingly much ado is being made about how this chip makes the new Mac mini X times faster than its predecessor, but then better than the previously Intel GMA 950 graphics chip is hardly cause for celebration.
That said, casual gaming at conservative resolutions and detail levels is certainly possible on the 9400M and the same couldn't be said of Intel's GMA 950. The selection of games for Mac OS is limited versus Windows, but titles such as Call of Duty 4, Spore and the ever-popular World of Warcraft shouldn't trouble the 9400M too much. nVidia's chip also offers GPU-decoding of HD video content, although as there's no Blu-ray drive option that's less useful than it could be; without using an external drive at any rate.
The Mac mini starts at £499 and for that Apple offers a 2.0GHz Core 2 Duo processor, 1GB of RAM - of which 128MB is assigned to the 9400M GPU - and a 120GB hard drive. 1GB of memory really isn't good enough, so the £40 2GB - of which 256MB is dedicated to graphics - upgrade really is a must-have, especially as the Mac mini really isn't end-user upgrade friendly.
£649 nets 2GB of RAM and a 320GB hard drive as standard. Both systems can be upgraded to a 2.26GHz CPU but the negligible performance increase brought is unlikely to be worth the £120 Apple wants for doing so. Likewise, adding 4GB of RAM is a further £80 on top of the 2GB configuration, but I doubt most Mac mini users would find it necessary.
If I were buying for myself, then, I'd plump for the £499 Mac mini, cough up £40 for 2GB of RAM and put the £110 towards an external hard drive, rather than upping the internal one, assuming that I found myself running low on disk space further down the line. Actually, come to think of it, I'd probably put the savings towards a copy of iWork '09 or Office for Mac 2008. Probably the former as it makes a nicer match to iLife '09 - which Apple includes with the Mac mini.