This is one of the lightest netbooks around at 2.2lbs (1.03kg = MacBook Air!) for 3-cell configuration. The adapter is very portable and slim at .4lbs (187 grams). It is an elegant, elongated wall wart that plugs into the wall. The plug can even be turned 90 deg to fit your outlet. I think it's the best thing about this Acer product, and they are using it for their newer 11.6" CULVs 1430 and 1830, too. I hope other makers follow this trend and eliminate the thick AC cable at the wall end.
The AOD255 itself is also very thin: at a time when Sony, Dell, and HP gets fat and lazy with 3+lb netbooks that measure 1.2" (3cm) thick, Acer cuts it down to 1" (2.5cm) from front to back (3-cell). At netbook scales, these minute differences in weight and size makes all the difference. To be fair, HP's latest netbooks are lavishly detailed and finished, at the cost of bloated size and weight; the Dell Mini 10 (1018) is passively cooled with only minimal hard drive noise, but looks (and weighs) like it ate the AOD255 for lunch. Toshiba NB500/520 is also needlessly heavy and bulked up, touting Harmon Kardon speaker quality (hint: it's not so good as those speaker grills look). Netbooks makers, Asus (see the EeePC 1018) and Acer excepted, seems to neglect the miniaturization opportunities afforded by the Atom platform. And people wonder why tablets and smartphones are in vogue.
When I bought this I thought it would be the closest I'd get to the VAIO X in terms of portability, a fair compromise at 1/4 the price, and approx. 40% more weight. Why did I want to return it then?
The Fan Noise.
The vent is wider at the bottom of the case, with 3 slits at the top clearly obstructing the airflow, creating a whole lotta turbulence noise, but no wind I can feel. It's like the architect routed your chimney stack to drainage pipe level. The heat gets recirculated inside, making this Atom netbook much hotter than my CULV Acer 1410 (U3500). What's worse, the noise is high(er) pitched. This is an obvious engineering oversight approved by a product manager who hears not, or a designer without common sense.
But still, if you can live with the high frequency noise when doing anything besides typing, and it's silent while just typing, in notepad, I think you'll appreciate its class-leading form factor. The ten or so tabs I keep open in Firefox, however, barely give it any idling rest.