you can really use this to delete any given folder that you need to delete recursively, but I needed this today, and google only gives me the answer for linux, and some strange solutions to do the same in windows.
here's a simple solution that works from the command line (the easy way, right?):
for /f "usebackq" %d in (`"dir *.svn /ad/b/s"`) do rd /s/q "%d"
more than anything I know I will need this in the future, so here it is for me, hoping that it can help someone else out there J