I just bought an Acer Aspire One 725 netbook. I installed Ubuntu 12.04 on it - there are two problems I ran into.

1 - The touchpad
The touchpad worked fine out of the box (it was disabled by default) but pressing fn+F7 solved that. After applying some updates however the touchpad wasn't working anymore. I found some solutions here on the forums but multitouch still doesn't work. It's usable but scrolling is a pain sometimes..

2 - Suspend mode
The default driver worked fine (with suspend and all that) but the screen brightness could not be changed. I installed AMD's driver - the brightness settings could be set then, but the suspend mode no longer worked. So at this point I have to chose one or the other I guess..

I'm looking for solutions on the forums, but all and all I definetly recommend you to give this netbook a chance. Everything else is flawless and Ubuntu runs like a charm. <3