Gavin, as Matt says it's because you're new. We've had an increasing number of people sign up to post spam, so for the time being anyway I'm validating new members manually. When I validate a member they automatically become a non-voting member. I then watch until they've visited the forums a few times or posted non-spam, to be sure they're genuine, then manually make them an ordinary member.
Do not go gentle into that good night.
Rage, rage against the dying of the light. (Dylan Thomas)