Web 2.0 - Connect Social Network Accounts

Apologies if this has been asked before... I've been manually setting up a load of web 2.0s and I've noticed that a lot of them now prompt you to connect your twitter or facebook accounts. Just wondering if anyone here thinks this could be utilised by the big G to detect whether or not it's a genuine/active blog? If so, do you implement this and how do you go about adding accounts? i.e do you create random twitter and fb accounts and get them to auto add/follow people etc?