Well, with the Free Pascal project I'm part of we have had this discussion some time ago too. SVN is a rather essential service as it contains the entire history of the project.
Outsourcing it means a third party gets a certain control over your history. This is not a problem now, but you can never exclude VA Software becomes a SCO or so.
Another issue to consider is Sourceforge means your work will reside on American servers. For OpenACS this might be different issue than for Free Pascal, but we feel that on our own server in Belgium we are much safer against mad American laws like software patents.
