What are the Assassinations like?
Are they more like AC2's follow this pattern to assassinate or AC1's figure out how to kill the guy stealthily or go all guns blazing if you want?
At my point in the game I've only done one "real" assassination and two contracts forced by the story, but it seems to be closer to AC1, though still not there.
im already on sequence 7. two real non-contract assassinations ive done u gotta be real stealthy. There are plenty of times where u have to be stealthy and plan right, and plenty of times u gotta be an all out power-house
In my opinion Brotherhood has the best story assassinations of the series. There are only 4 of them really, but they're all unique and actually challenging. They utilize the same bite size mission structure of AC2 but I think its done better here.
No, you don't get to plan out your assassinations after investigating but I think the game is better for it. It kept me on my toes. But I didn't think the gameplay structure of AC1 was that great, so I'm alittle biased.
Anyway, the three main targets are epic and there are other "set piece" missions that are also equally thrilling.
yes the real assassinations are more challenging than ac2. but only 4 of them? 
I was fine with only 4. AC2 had way too many, resulting in some pretty underwhelming missions. The story flowed better too, if you ask me.
Sure, I would have loved more, but given the time they had, I'm pretty happy.
Some of the other missions in the game are also noteworthy, even if they arent assassinations. The 2 of the Lairs of Romulus were absolutely brilliant (the others were good but not perfect) and some of the Leo war machines were great too.
I haven't even started the optional assassination contracts and thief/courtesan missions, which I've heard are pretty fun.