As the title says really, I've had this in a few games and I find it quite annoying that I can't cancel the move (pressing escape doesn't work).

You talking about Live or Online/Correspondence?

 The rule says you must promote.

Live chess, sometimes when the time frame is really tight I might think the pawn promotion is a good idea but then the interface doesn't let me change my mind (ie. cancel the move...)

refresh the page

 To cancel it, is like a take back move, is a no no in the live chess but you can in the unrated game.

Once you move a piece as stated above it is considered a move. Best Idea if you are playing Correspondence is to make the moves in Analyst window.

I have it set up so that no move is registered until the "submit" button is pressed.  This includes pawn promotions.  Probably a good idea, to avoid mouse slips.  Now if you have it set up the same way, and you have promoted a pawn, but not yet hit the "submit" button, then all you have to do is make another move, and the first one (pawn promotion) will become null and void, and the pawn will revert back to its prior position on the board.  Failing that, you can leave the game, and then enter it again, and you will find the pawn right back where you left it.

Sorry for the confusion guys but i'm talking about LIVE...

And I'm also talking about when I've moved the pawn into the area where it can be promoted.. technically I haven't submitted the move yet

There's your problem. You moved the pawn, you're committed I'm afraid.

Thanks