I like Nokis Pulse specially because you have control to choose what you share and more important, to whom.
As some people already said, this would be more efficient if there would be a way to connect with people not using Nokia phones (maybe opening a Nokia account but using pulse from their respective phones).
I have invited some friends and they like the idea, but don't use it mainly because they have android or iOS and to them it is pointless. I hope this helps.