Here's a nice article on selecting a CRM solution, from InsideCRM. I know it's a nice article, because I'm quoted in it. (You'll find me under point #2.)
There really is a lot of good information in here, even when it's not me being quoted. If you're in the market for a new CRM system (or association management system), this article is worth a read.
(You'll find me under point #2.)