As the Sun reminds us today: celebs are hot for Twitter and Facebook. Lady Gaga, Justin Bieber and Stephen Fry have massive fan/follower bases that hang on their every Tweet and update, a potential bonanza for brands with Twitter-savvy celeb spokespeople. Ah, but not so fast. New rules in the UK designed to protect the public from the celebrity-endorsed Tweet could impact this practice before it gets a chance to take off.

Today seems to be all about Twitter. In the wake of the terrorist attacks in Mumbai, news of which spread by Twitter well before the mainstream media started their coverage, Michael Arrington at TechCrunch argues …