After using Evolution for quite a bit to read my work mail, and after some deliberation, I decided to switch to Gnus, as I'm already doing a lot of my editing and what-not inside Emacs. I also wanted to keep a small memory footprint, as I'm using my work laptop as a development machine too— Firefox as it is grows to 40% of the machine's memory when I use it, and adding Evolution would mean that running builds on the machine would consume swap as well.
So far so good. I really like the fact that Gnus learns from my reading habits— whether a thread is "interesting" or not, or whether a mailing list post is from someone I don't like to read. I have my mail grouped according to mailing list. I'm currently migrating some of my mailing list subscriptions to my work email, so I can see whether or not the Gnus environment helps in managing the relative flood of email from these lists.
In any case, for those interested, I have my .gnus file online, for those interested in reading my Gnus preferences. I have some pretty nifty nnmail-fancy-split rules in there. Right now, I don't have to add a new rule when subscribing to Google Groups or to Yahoo! Groups— I just subscribe my address to the related group, and the related Gnus group is added automagically.