I got this PM from system today:

From System at 2006-08-30 18:07:37 (3 hours ago) GMT

Doors are going to be shut as of this friday....invite only then Sorry
If you have freinds or family who want to join get them in fast as once shut you will only be able to invite so many ..i think 2 at most !!!!
We are already over the 35,000 (8000 peers) we said we would close at for a while.
We are still getting approx 200 new users a day join the site but we need to start weeding out the users who dont use there accounts or cheat or leech.
Once we have had a time of closed doors we will try to open again.

Signups are open GREAT site