I’ve just finished writing the documentation for the new device orientation support added in Gecko 1.9.2 (Firefox 3.6). For starters, DOM windows can now receive MozOrientation events.
There are several new interfaces, as well:
I’ve asked for feedback and technical review from dougt among others, so it’s possible this material could change as I receive corrections, but based on my reviews of code, samples, and existing material, this should be fairly accurate.
This is going to be a very cool technology. Obviously it’s especially useful for mobile users, but laptop users may get some use out of it as well. It has a lot of potential both for user experience improvements (such as rotating the user interface based on the orientation of a mobile device) and for web gaming.