I'm fairly new to the game, and I don't feel like I've explored enough of RTW to get super-excited about the expansion pack. There are still a lot of factions I haven't tried playing yet. So normally I wouldn't jump right on the exansion pack.... unless.... they manage to improve the battle AI. That's the one thing that would get me whipping out the credit card right away. It would be nice to see the AI treat its army like a cohesive whole, instead of the disjointed "every unit for himself" feel of the current AI. So that's what I'm looking forward to, if they can pull it off (and I know AI programming isn't easy).

Okay, I guess I'm also curious about what the night battles will look like. I wasn't happy to hear about that feature at first. I play the game in the daytime sometimes in a brightly lit room, and I don't enjoy games that are too dark on my monitor to see anything. But the screen shots look pretty nice so far. Hopefully they've found a way to make things visible without losing the feel of night time completely.