Still a massive problem. I have email verification, question & answer. AND I ask people to write something about themselves to verify they are human. But still on average 1-2 spammers a day get through the net.
Mostly they aren't the obvious ones they are the cunning type who reply to posts with something like "Thanks, that's very interesting", then include a link, of course.
The problem being that I have to verify all registrations manually, which is a pain for new users as once they have to wait a few hours for me to get out of bed, they may have lost interesting in posting on the forum.