I have been using Ubuntu for 3-4 years now and have been using it for everything from day-to-day stuffs to development. I am quite happy to see how Ubuntu has matured during this time frame.
But, I wish some improvement is done on improving hibernate. It takes ages to hibernate and system sometimes freezes. Moreover, my experience with battery life on Ubuntu vs Windows suggests Ubuntu manages power poorly.
I haven't used Unity yet but look forward to trying soon.
I hear you on hibernation issues. Windows 7 boots in no time from hibernation, but Ubuntu (10.10) takes ages. I don't hibernate at all (preferring to switch my box off) because of this.
I've read that Ubuntu 11.04 uses an updated version of the Linux kernel that solves this issues, I'll try it out when it's released.
Regarding battery life, I get three hours out of mine which is similar to what I got with Windows 7. (However, Ubuntu's power options are nowhere near as fine-grained as Windows 7, at least in GUI form.)
But, I wish some improvement is done on improving hibernate. It takes ages to hibernate and system sometimes freezes. Moreover, my experience with battery life on Ubuntu vs Windows suggests Ubuntu manages power poorly.
I haven't used Unity yet but look forward to trying soon.