- Not user friendly

- (in my case) My wireless drivers keep disappearing however sometimes they reappear and decide to work. Also graphics card drivers (x3100) work, but you can't use video and compiz at thye same time. If you can't get the drivers right (this goes for the devs,the hardware manufacturers and anyone else), then ubuntu will never take off as "joe blogs" won't want to use something which won't fully utilise their machines hardware, or even work. (these two problems may make me give up my 2 year struggle with ubuntu :/)

- updates occasionally break peoples system and we all know that not everyone backs up their data...

- not enough gui's to make the new users feel at home with the OS (ties in with not user friendly)

I really like ubuntu, but i just wish the effin drivers would do as they should...