I did it. Finally I moved from Subversion to git. Until today, ZMPP was the only larger project maintained by me that was still in a Subversion repository. To be fair, in the two years I used it for my projects, I have never really experienced larger problems. It felt exactly like it was intended to be: A better, more modern CVS, and it has great tool support as well, something where git could still improve.
Still, after using git in parallel to svn and cvs for about a year now, nothing really beats the joy working with a DVCS, even when used solely through the command line. Personally, the way git handles branching and merging is perfect for me: it really invites one to make wild experiments. Another nice thing is that due to its decentralized nature, it is much easier for me to add ZMPP to my Hudson setup, work on my local copy and just push the changes to Sourceforge when I think they are good enough.