Purchased one of these (1GB, 120GB version) last week and it arrived yesterday and I must say I think it's great. Not only does it look cool it's really easy to get running and use. Wireless connection was a breeze and basically the thing just works straight out of the box.
To test it out I played some MP3's and tried it with the BBC's iPlayer and it worked perfectly (with headphones anyway, the built in speakers are very poor).
The web cam, contrary to some reviews, is actually really good, I tried it out with the built in messenger and was chatting with my daughter on MS Messenger in no time. As the boot up is so quick the Acer One is the ideal way to stay in touch with friends and family.
The operating system looks a bit childish and it's very restrictive when you're used to using something like WinXP.
Also the noise from the fan is quite loud for the size of the unit. And as everyone has probably commented, the battery is pretty dismal at around 2.5 hrs.
But overall if you want something to surf the net, read emails, write documents and all the basic stuff that most of use our PC's for while your on the move and you've got another PC for the heavy stuff, this gizmo is great.
It's light, compact, cool looking, quick to boot-up and good value, what more could you ask for.
Update 12th Dec:- still loving this machine but have now put windows XP on it as the Linux became a bit of drag, just making a shortcut is a major job.
With XP on the other hand it's turned it from a little netbook to a cool little laptop. Still boots up in seconds, it's a great little machine. If you're wondering whether to buy or not I would definitely say buy it you wont be sorry.