Merging and branching in Subversion 1.5
The forthcoming version of Subversion (version 1.5) promises a few niceties, but the best of the lot will be the long-awaited merge tracking feature.
For example, one cool trick is that you can now repeatedly merge changes from a branch into the main trunk (or another branch) simply by specifying the branch where the changes are coming from. In current version, you need to figure out exactly what change sets you want to merge back into the trunk, which can be a real pain.
There is also a nice little Eclipse plugin which makes handing your merges from Eclipse a whole lot easier.
For more details, check out Merging and branching in Subversion 1.5 on JavaWorld.