I used to use the svn over at wowace but it got wonky and annoying during the great-move-to-curse and I hated what they did with my mods over at curse b/c of using the svn -- since curse went all money-grubbing-jerks and revamped the site to annoy authors and users alike, I've avoided it.
I started to use the svn here at WoWI but decided that, as I'm the only one working on the thing, it's just not worth the hastle as I can do version-control all on my own with just about as much fuss and annoyance
I would suggest using only one svn -- pick your favorite spot -- if you want to use one at all, then making a package that you upload to other sites. The svn is really for your convenience so use it as whatever aid you find it to be and don't make more of it than you need it to be.