Pinterest has dropped its invite-only policy, opening its doors to all comers. The photo-sharing social network had previously kept its population in check by requiring invites, but CNET reports that Pinterest has increased its capacity to accept new users. The sign-up process never took especially long, but open registration could help bolster Pinterest's population. Not that it needs too much help — in its invite-only state the site saw a daily active user count of about 1.1 million, though that's down from a high of around 2.2 million once Facebook's Open Graph disabled auto-posting. The ramifications of opening the floodgates to the general public should be clear soon.