[adrianhoward]

Just to repeat something I mentioned in the comments on Dan Shipper's, there is actually evidence that self-set public goals can make it less likely you complete the goal.

(the theory being roughly that just stating it publicly feels like making progress, so you're less likely to actually make progress.)

See http://sivers.org/zipit for some background info.

There's been more research but I don't have the references to hand ATM.