Saw this announcement today: http://www.engadget.com/2010/12/06/g...p-drawing-and/

Google maps is introducing an HTML 5 version of maps with offline map caching, on-device rendering (supposedly reducing data transfer amount), and offline rerouting using cached data.

I hope this will be made generally available. It would be a perfect fit on the N900. If anyone spots a url for this, please post it here!