Well, I upgraded one of my main workstations here at home to the Edgy Eft. Upgrade is easy:
gksu “update-manager -c”
After a few hours of slow downloads and some dialog confirmations, your Dapper Drake installation will be upgraded. Firefox 2.0 is one of the major app updates. Lots of little tweaks. Amarok looks like it's been heavily upgraded. VMWare Workstation 5.5.2 no longer works in Edgy Eft, but it looks like VMWare is working on resolving that issue. So far so good. Man I love Ubuntu!