300+ subs have already announced that they are in it for the long haul, prepared to remain private or otherwise inaccessible indefinitely until Reddit provides an adequate solution. These include powerhouses like:
/r/aww (34.1m)
/r/music (32.3m)
/r/videos (26.6m)
/r/futurology (18.7m)
Well, I just ran Power Delete Suite and removed my 11 year old account. It was good as long as it lasted.