I've been a Firefox + Thunderbird user for years now, been following each and every release. I like the combination of two different utilities. I never did like the Netscape suit (you remember Netscape Gold ?). Two lightweight utilities that supply most all of my needs. I completely abandoned Outlook Express once Thunderbird was stable, though I still use IE most of the time.
I was especially excited when looking at the release notes before downloading the latest version of Thunderbird (congrads on finally reaching version 1.0), hear that it supports RSS, to me reading RSS in the Mail reader is the most logical thing, I was going to purchase NewsGator, but after getting the feel of it on the trial version I decided it's not yet where it should be. Since then I've been using SauceReader (I've used SharpReader before that).
But the first look at the interface was disturbing, it wasn't quite clear how to start using RSS (you need to create a new folder with the type of “News & Blogs“), NO OPML importing - A big miss for mozilla! how am I going to import my current blog roll? one by one for some 300 blogs? not to mention no commenting or composing capabilities - Mozilla just wants us to have read only rights on blogs.
It seems like a rush to put in the functionality without filling some basic needs of users, just so that they could say “Hey, we did it! we have RSS!“, and really it's a shame because a slightly longer delay on the release would have enabled them to put out a more complete solution.
I won't be using Thunderbird to read my RSS anytime soon.