Don’t upgrade to hardy yet!
If you are thinking about upgrading (don’t ‘alt+f2’ and then gksudo “update-manager -d” ) well don’t do it yet.
I did last night, besides it having to download about 1gb and taking about an hour to run it’s installer, it can break you desktop.
I couldn’t get the gnome daemon to work, and x would fail allot.
It’s only a few more weeks till the final (read stable) version comes out.
Just a heads up.