I wouldn't mind the shortness if the story was good, which it really isn't. It's very predictable and goes pretty much like Mafia 1.
M2 is the kind of sequel that is made to milk the success of the first game, not the kind that tries to top it.
EDIT:
Here's few things that tick me off in it.
Story is pretty vague and predictable as I mentioned already. Also, you don't get the sense of achievement as you did in Mafia 1.
Cops are idiots, you can smash lampposts and stuff right under they eyes and drift and all that, they don't mind. Also, here's an example from one mission: Two cars were chasing me with guys shooting my car with tommy guns and what not, I drove past police car, he didn't react. I slowed a bit and one of the chasing cars hit me, this got the cop's attention, but just because he wanted to arrest me for damaging another vehicle.
The next one shows how lazy they devs were. There's this redhead chick you see throughout the game in various cutscenes, do me a favor and see how many 'clones' of her you see while driving around the city. I managed to see atleast dozen of her in 100m while driving around.
The collectables (playboys in this case) are hidden IN the missions, not in the city like any sane dev would do.
Gameplay is good, I give them that and it looks pretty.
But, like I said, just an attempt to milk the success of Mafia 1.
EDIT2:
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They even got the balls to have you and your mobster friend be the ones who kill Tommy Angelo in the end of Mafia 1.
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