Facebook, I resisted for years until finally a friend convinced me to register last year.
'It'll be great for your business!' she claimed...
Well, it has been, I've slowly grown my friend list and am able to use my business page to keep customers up to date with what's happening in Karri Tree Lane world.
It is also a huge timesucker and is crap in comparison to Real Life Interaction. I am wary of my family's safety, and have pretty tight security settings.
Used appropriately Facebook is great, yet so many people seem to be able to get in the poo through being naive or stupid, I am really pretty unsympathetic!
Twitter... I am pretending to experiment with twitter, tbh I just don't understand the appeal. I have my business facebook page set up to automatically update twitter, this works well enough for me ;) I already have a hard enough time keeping up with the emails that I'm sent everyday never mind interacting with people on both facebook and twitter.
In a library setting I suppose I can see the benefits of both Facebook and Twitter, depending on the demographic that you're trying to engage with. You can follow my Web2.0 twitters at @2point0beth