In comparison to OSX and Windows running on the same hardware, Ubuntu is worse in every meaningful way. Power management is terrible, window management is terrible, the Ubuntu software center is slow as hell and has no selection (amount of useful software is a huge concern, actually). It lacks polish in general, things that people have come to take for granted in their OSs are missing or badly implemented.
I'm sure the argument will come that most home users only need a web browser, so the software selection isn't a problem, but at that point you might as well just use Chrome OS and get something that actually works.
I'm sure the argument will come that most home users only need a web browser, so the software selection isn't a problem, but at that point you might as well just use Chrome OS and get something that actually works.