Subversion is a great version control system. Something that was really annoying was lack of automated merge tracking. In short, this means that when you have several branches, and merge changesets from one branch to the next, Subversion does not keep track of these merges. When you do another merge with stuff that was merged previously, things get merged twice and weird things happen. This currently means careful administration or usage of weird scripts that will do the micro-management for you.
Subversion 1.5, the next version, will contain built-in automated merge tracking! Because this is such a major feature a new project is opened for the merge tracking beta test. If you are interested in this new feature be sure to try out the beta and let them know about your experiences.