That is still undecided. I would rather make it git, main reason being that it is possible to merge in whole histories from (possibly personal) branches into the main tree. That'd be very handy when developing e.g. the multicore support, since the initial development can take place on a separate branch without upsetting the main tree (things probably won't even compile for several weeks), and then rebased and merged with it without losing the history (i.e. it all won't become a gigantic commit with a single laconic message like "Multicore support."). Afaik svn doesn't handle that, but maybe I'm wrong?