I have been an adamant Ubuntu supporter since I was converted to it – but I have been quite disappointed with Feisty (AKA: Version 7.04). Not Feisty itself, but the process.
Read it here
A week or so ago I tried to upgrade to Feisty from Edgy using the Update Manager (as suggested in the install instructions). However, the update manager kept providing me errors that several file locations could not be reached for download. The update manager would then quit, and Id have to try again. I assumed this was just a busy server time, but after nearly a week of attempting it, I decided it must be more than that.