Ok, that freaked me out a little. I like to stay up to date, but I can’t live without some of my plugins.
The good news is that there is a plugin compatibility page where they are trying to list all the plugins that work, or don’t work, with WordPress 2.1. The biggest red flag I saw was Ultimate Tag Warrior. Give it a few days though and it’ll be ready to go.
If you don’t see a certain plugin on the compatible page, and you can’t find updated information from the author, drop the plugin name below with a link to it and I’ll see if I can’t get it tested for you.
Overall WordPress 2.1 looks nice, but I’ve only had it installed for 10 minutes on my test blog.