Okay? Personally that doesn't really change things for me any. I'm just stating I like Ulfric more as a character, i'm not saying he's the reason I choose the Stormcloaks, though of course it helps from a roleplaying perspective. Thing is, Ulfric can be pretty dry himself at times - generally when its appropriate. He has range in his emotions and reactions. It actually shows what a good job Ulfric's VO did, because I really dislike 'the Governator' and Ulfric's voice reminds me of his at times. Yet, somehow I still really like the character, despite this bias. In contrast - I want to gag most of the town guards, because they sound even more like him and only spew stupid comments.
Tullius seems to just seems bland. He only breaks out of his 'stressed and frustrated' tone a couple of times, and thats when he's berating someone or yelling. I found the same sometimes when he played Colonel Tigh, but generally he was pretty awesome in that role and did emote more. I think it is simply that he isn't a big game fan and phoned it in somewhat. That may not be fair though; I just never felt his character, even as a stern General. Maybe it was the sound room they used.
I also feel Galmar(sp?) while not someone I would want to share a drink with is more interesting than the Legate. Her entire character seems to be 'A typical Nord that supports the Empire, and is also a covert Talos worshipper'. The conversations between Galmar and Ulfric are facinating, whereas those between Tullius and the Legate just didn't do anythign for me other than give me a general idea of how things are going and where i'm going next.
OMG it's like we were separated at birth.

I agree totally, having done both sides I was terribly disappointed by the Imperial playthrough. I really hoped and expected that there would be something to make that feel worthwhile from the "fun and interesting" perspective, but... no.
Ulfric has a way of making you feel valued and appreciated, that your allegiance means something to him. (Even outside the CW quest... compare for instance the differences in dialogue and attitude between when he makes you a Thane, and any other Jarl does it. He also doesn't stoop to calling the rest of his subjects "common rabble," which even Balgruuf does.)
With the Imperials... meh.