I believe this really needs to be changed still. I don't think this forum will ever grow to what it was if it takes so long to wait to make multiple posts. I understand the spammers are really bad, but there are other ways to combat them. I recently registered at another aquarium-talk site, and one of the requirements to register was to type "the third letter of the alphabet 12 times, the seventh letter of the alphabet in upper case, then the number of front legs a dog has". Just something simple like that during the registration process would really be good.
Require a CAPTCHA type thing for every post. That's how it is on some sites and it's really not that bad. But the inability to post back-to-back is super frustrating and needs to be changed ASAP.