Captain Crunch and Shrapnel put together a compilation of the most tactical jumps yet to be discovered in Halo 3. Credit to both of these guys for discovering a new technique and applying it in an innovative way. Check out their video:
Many of these, and the techniques behind them, are sure to advance the game dramatically. Surely a detailed tutorial will be coming along very soon. As of now what we know is that jumping off of these seemingly flat walls involves hitting a corner and crouching and uncrouching in a certain way. The technique has yet to be given a definitive name. Thanks to both of them for this information.