Like the first one?

nope

The answer is no in as much as any AAA game is repetative, but I shall point you to the Giant Bomb Video Review

Yes and no. The main story isn't repetitive at all but if you want to do every side mission and find all the treasures its very repetitive.

Well, you kill a lot of dudes but that's a given.

no, but is there depth to the gameplay? not really. The combat is still attack, counter, and so on and won't get much deeper, the freerunning is still basically hold down a few buttons and press in the direction you want to go (although they attempt to make it more difficult, the freerunning never gets hard, not even in the supposedly difficult assassin's tombs). Even though i kind of noticed all this, I made it through the whole game without ever feeling that the gameplay got tired or more repetitive. although the gameplay is simple, I had fun with it the whole time, so repetitiveness wasn't really an issue for me.

Don't do what I did and get bored enough to take on every viewpoint one after the other.

not as repetitive but can still become so

Haven't played the first one much as i got bored of it, but the second one is pretty promising so far! 
Seems quite different in a lot of aspects, combat, stealth and general leaping from roof to roof. Si far, so good!

i havent played it, but im wondering what you mean by repititive.. do you mean the nature of the missions  ?

Not at all, in some ways I wanted more of the experiences that we only got once (ilke the road trip with Leonardo Da Vinci).

Assassin's Creed II has a very driven storyline.  You will find yourself (unlike the first game) knowing exactly where to go for your next mission.  You aren't given really that many options, but this is a good thing considering the lack of variety in the original Assassin's Creed.  AC II's mission structure feels a lot more like GTA than AC1's did.  Also, it's a much, much better game overall.

You could make the game repetetive by doing the same thing over and over for a bit...  but you would have to choose to do that. Otherwise its no more repetitive than most games and nothing like the first one.

I think that to call every game repetitive on the grounds that they have a core gameplay mechanic that is utilized throughout the game is ridiculous. That, for the most part, is how video games are made. That argument suggests that in order for a game to not be repetitive, it needs to constantly change the mechanics of the game, which more often than not is a recipe for an unsuccessful game unless you're making some kind mini games collection or something, a la Mario Party and Wario Ware. But, hey, I don't know maybe someday there will be a game that can do that without making the experience seem like it lacks focus and cohesion.
  
While there may be some validity in the argument that pretty much all games are repetitive in so much that you do the same sorts of things all the time, I think it ignores the context those gameplay mechanics are utilized. Why not extend the argument even further and say that video games as a medium are repetitive because you perform the same physical action--button pushing, analog stick manipulating, Wiimote waggling--over and over again.
 
I think essentially what  gamers like myself and Paintedelta are asking is if the core gameplay mechanics in ACII are employed in different ways that contributes to an overall feeling of variety. In the original AC it seemed like I was doing the same mission over and over again because the game seemed to adhere pretty closely to one main mission template. 
 
A good gameplay mechanic, of which the AC series has, can be rendered dull and repetitive if players aren't allowed to use it in a variety of ways.