Whilst it's pretty and does the job generally, don't think about playing games, loading any software or expecting i-tunes to work.
Don't think about changing hardware without issues, or getting drivers to work for that matter. (hardware is linked to o/s serial, make a change = re-register with M$)
Very secure compared to XP (Only matter of time), but very much a pain in the neck.
I'd suggest anyone buying a PC now stay away, demand XP and upgrade in a year or so's time when they've sorted the mess out.
Another point is pretty much all CPU's are 64bit, so really to get the most out of it you should use a 64bit o/s. Most vista bundled in seems to be the 32 bit version.
Someone was questioning why no disks anymore to restore from. That's been happening for a while it's M$ anti-piracy idea. Not sure if you can demand the disks anymore.
No disks = No copies = F'd user = Tech Support Cash from phonecalls.
Answer = Format disk, carve partitions, load xp, linux and vista (if you really must show your friends how pretty it is.)
Not had any issues with ordering Dell pc's for others, hardware's generally of good quality and so is the build.
Saying that I always build my own pc's so I know what's in them, and I can choose to avoid prebundled cack. Plus I don't pay for it when I get a new pc up and running.
You'd be suprised how easy it is to build a pc.