I just upgraded from Thunderbird 2 to Thunderbird 3 on my Vista machine, and I like it a lot. If you haven’t heard about version 3, I recommend that you upgrade. I have not yet tried it on my work machine, running the old version 8 (“Intrepid”) of Ubuntu; if you have experience with this, I’d appreciate hearing about it.
Some cool things:
Search is much faster, due to indexing. (When I first brought up version 3, it spend a long time indexing, but that’s because I have a huge number of saved messages. I was able to use it while it indexed.)
When you select several messages, it displays extended summaries of all of them: whom it’s from, date, and the first few lines.
If you double-click on a message in the summary line, instead of creating a new window, it creates a “tab” in the main Thunderbird window, a lot like Firefox tabs.
The operations on a message being read are now down where the message is, to the right of the header display. This seems a bit more intuitive, although I don’t think it matters much.
Archive: The new “Archive” command moves the message into a folder. The folder is the subfolder of a new top-level folder called “Archive”. The subfolder’s name is the year from the date of the message.
If you use the word “attach” in a message you’re composing, it brings up a fairly unobtrusive bar a the bottom saying “Found an attachment keyword: attached” or whatever word you used (you can control the set of keywords), followed by buttons for “Add Attachment…” or “Remind me later”. When I used Thunderbird 2, I had an addon called “Attachment Reminder” that would pop up a menu when you clicked “Send”, asking you if it was OK. That’s more obtrusive, which you might or might not like.
One bad thing:
There’s no more “Forward all as attachments”, which let you send a message that contained many attachments, namely everything you had selected in the summary pane. I have used that many times.
My favorite add-on is “Expression Search”, which provides a powerful and concise way to search. The best thing is that it saves you from having to use the mouse to select the type of search to do (the “magnifying glass” dropdown in the upper-right search bar).
I also like ConfirmFolderMove (helps prevent accidental “move folder” operations.
(I’m just starting to try MailClassfier, which would be very helpful if it turns out to work. But the first time I tried it, it was analyzing all of my mail, and at the end of this slow process, Thunderbird crashed. And when I restarted it asked again to analyze all mail, so apparently the results were not saved before the crash. I’ll keep trying to make it work.)