Ran the installation, which was relatively painless.
A small number of my add-ons didn’t autoupdate. Tab Mix Plus was one of them, which was a bit annoying at first.
RoboForm required a manual download of the XPI.
ImgTag seems to not have been updated. A shame — a useful widget (it creates a context menu of choice to put an HTML IMG tag of the clicked image into the clipboard, very useful). I’ll keep an eye open to see if/when it’s updated.
I haven’t used Resizeable Textarea (which, basically, lets you resize any HTML form field) as much as I used to. I’ll decide if I need to update it; it sounds like someone’s hacked it to work, so I expect something to work on it pretty soon.
Tab Mix Plus is updated through non-automated dev build. While FF has added additional features to tabs, they don’t match what TMP gives you.