This time around Ubuntu 10.04 is touting some great UI and design changes. Moreover, this being an LTS release, there are all the more reasons to go with the fresh install route. So if you decide to do so, come the 29th, here are some of the Ubuntu applications that you might want to install on a fresh Lucid Lynx install.
Nice list of stuff you'll want to install after doing a fresh installation of Ubuntu 10.04. If you haven't yet tried it, Chrome is REALLY nice on Linux (though Firefox is still my daily driver, it's nice to have an alternative browser particularly as a web developer), VLC is a must have, and if you weren't aware Ubuntu no longer ships with The GIMP pre-installed.
I could take or leave the Checkgmail but it's a nice example of what can be done with the new MeMenu in 10.04, but Gnome Do is great if you haven't tried it (I just learned about this one myself a couple of weeks ago), Beagle is a really nice Spotlight-like app, and hey, if you want your Linux box to look like a Mac, there's even a Dock app.
The only one not on this list that I think should be there is Back In Time (http://backintime.le-web.org/) which is very similar to Time Machine on the Mac. I have yet to try it on 10.04 but it was just set and forget on 9.10 so hopefully it works on 10.04.