Knocked Up falls in the category of vulgar comedy that overshadows (and admittedly, at times, can reinforce) a nice, feel good movie with the same story of ultimate redemption.
It had at least one character from Superbad (review) and a similar feel to 40 year old virgin (review), but I think it was the best of the 3.
It was cute, but I wouldn't necessarily highly recommend it. 3 stars (probably 2.5)