Like I said, the main reason to upgrade is for better comment spam prevention. The brilliant MT Blacklist (created by Jay Alen who now works for Movable Type) worked pretty well with MT 2.6, but the new version of Blacklist has improved features that only work with MT3.

The upgrade was relatively easy, but I did experience a little glitch. When I rebuilt all the files, the comment count reset for all entries. So, if there were 10 comments on an entry before, the count would reset to zero and a new comment would register a comment count of 1 and increase from there. Unfortunately, I don’t think there is an easy solution unless you have a backup of your database. Yesterday I switched the servers that our site is hosted on (for unrelated reasons). Since I was reuploading everything to the new servers, I could do a clean install of Movable Type 3. When I imported all the blog entries, all the comment counts worked correctly. The only new problem I encountered was that I lost all the passwords for our authors. The solution was a very handy plugin called MT-Medic that allows you to change passwords for different authors. MT-Medic also has many other great administrative features.