A World of Warcraft Blue poster, Ghostcrawler, has spilled a bean or two in the forums about the dual talent spec option that we've all been craving and that we will learn more at Blizzcon:

Furthermore, don't expect us to be ripping up every other talent tree in the game at this stage. We will continue to change talent effects before Lich King ships, but don't expect a lot more massive rejuggling of the trees themselves. The dual-spec feature will shine more light on talent design (more on that at Blizzcon) and we'll have a better idea of what we want to do with trees when that goes live. Some talent trees are nice and lean, and some probably have some points we could trim here and there.

The dual talent spec is the idea of a character having two pre-set talent specs that could be switched out easily (but might be costly?). If you have a raiding spec and a PvP spec you wouldn't have to keep re-inputting them at the trainer, you would have them pre-built for easy transition. This should be an awesome upgrade to what is now an archaic system (the game is four years old in real time, 200 years old in internet time). I'm really looking forward to learning how this new system will work.

For additional talent information from Ghostcrawler, head to the official forums.