Because the SourceForge.net anonymous CVS gets still not synced with the developer CVS, I've setup a nightly snapshot:
http://doc.b2evolution.net/b2evo_HEAD_snapshot.tgz

It gets exported from developer-CVS every night, if there are changes in HEAD.

I'll probably remove this service again after SourceForge gets things straight again with their CVS service, so this is meant as a temporarily help.