For any ladies who are thinking about uploading a verification face photo but wish it to be kept private, it's worth drawing attention to a Greasemonkey script which is currently being passed around the houses that allows anyone using it to view these images (it was originally being mooted as a way to spot fake profiles since it also allows users to see how many unread emails/booking requests a member offering services had, and needless to say the ability to view face pictures which ladies had uploaded in good faith believing they would be secure has not exactly been shouted from the rooftops). The script is apparently no longer available from GM, but it's unlikely that we will have to wait long for a replacement, and even if there isn't one the first will be spreading like wildfire.
As Pandora said, some people find the site very lucrative and whilst I've heard a couple of tales of people having their credits pinched following an undeserved deactivation, I wouldn't have thought it was that common provided you stay within the rules. If you do anything which earns you any amount of credits, keep spending them or draw them out/cash them in, whatever it's called. I would personally strongly advise against sending the personal details they are wanting for this 'full' verification though, and would feel exactly the same way about any random offshore company which contacted me asking for them.