Back when 10.10 came out, I almost left Ubuntu for good because they left out install support for those of us with nvidia drivers (only on install...i.e. blank screen but OS works).
So when it came to 11.04 I almost skipped it but obviously..that didn't last long.
Like many, I hated the Unity UI at first but after switching back to gnome....I realized I didn't want to have to customize every little toolbar setting, option, etc... to my liking. With the exception of a very few minor settings (that no OS would ever get right for me out of the box cause it's pretty much an OCD thing) everything was just there an ready to go which I really like.
Display\desktop real estate...while distracting at first...the launcher bar fits perfectly where it's at and serves the ultimate purpose flawlessly. I'm also big on digital artwork and love having a good wallpaper up and it doesn't even take away from my occasional eye candy fill.
What people will definitely get hung up on: the toolbar at the top.....I think once people realize that it automatically works directly with whatever application and task you are performing...they will be much happier --> that and I think they will come to love the disappearing menu options.
I didn't even have to mess with the "nomodeset" option or hold down shift on startup to get into the grub to get my nvidia card up and running. It was a flawless install this time out and I am loving this new version the more I use it.....THIS is what the last release should have been.