I dont know if its still the case, but I know in years past they were quite a target for spam bots. These are automated computer programs that use false information to register new accounts by the hundreds to spam forums with ads and google exploits.
Thats why the registrations have to be filtered by hand, and when under attack its a big job. I've done it. When going through the days list of 600 registrations the mod only has a second to judge each 'person' so try to use a real person sounding name, not broken up strangely with periods or with numbers on the end, and use a real person sounding email address not from russia, ukraine, or romania.