I came across this article on Cnet today. At least for me speed is not the only thing. I use Firefox exclusively (at home and at work too). I like Firefox because of all its features and all the add-ons I get with it. Firefox has such a huge collection of add-ons.
I have been trying flock from time to time to see how it is progressing. It has now become very very impressive, with Facebook, Twitter, Picasa, Flickr, Delicious, Gmail, Yahoo! Mail integration.
Well, whenever I think of a problem, I always check if anyone else encountered it before. And Google is your friend here.