Your post recalls my current situation...
Last Sunday I woke my deuced Mac(hina) - exact same model as yours...purchased Feb 2009 - from sleep, and although the backlight kicked out almost immediately (my desktop was visible) I discovered after some experimentation that I could run at a maximum of 3 ticks of brightness.
When I woke my Mac from sleep on Monday the backlight wouldn't come on at any level of brightness..immediate trip to the Genius Bar where the diagnosis was a bad inverter and cable...3 to 5 days turn-around.
Five days later I was told that changing the inverter and cable had not helped...that my display was going to be replaced. (Any idea why the entire display, or is the backlight not replaceable on its own?)
I'll get the MacBook back later today and confirm that the display actually was replaced, but, for the moment, thank goodness for AppleCare.
Good luck.
