About the issue of going OTD as a cause of going facebook, it is definitely true. I heard of 3 incidents in which frum girls created their own profiles just for the ‘kick of it’ and were then dragged into a different way of life with no way back. 2 of them hooked up with ppl they would’ve never gotten in touch with if not their facebook profile.
This is one of the reasons I don’t have a public facebook/twitter profile.