FourSquare
If you haven’t checked it out yet you should. It will feel a little like Facebook and Twitter did before everyone joined in but the potential for FourSquare is huge.

As with all new social media I’ll be jumping in feet first so if you want to chat about FourSquare or any other digital PR just shout - Tom on Foursquare
You can also follow Leader on Twitter or even me directly - @TomGrocott