Its a good way to pass the time when im at work or in digs, and its also useful technically, so I certainly have a use for it and also get enjoyment from it, I wouldnt say "addicted" though as that implies that you cant manage without it, and also that it does you harm in some way.
So if for example you were at home with your mrs and instead of wanting to go and fuck her you were sat on PF and it ruined your relationship, that would be addicted.