I saw it this afternoon. There are a lot of funny lines and sight gags but, overall, it's not a particularly good movie. I laughed a lot, but walked out of the theater thinking I don't ever need to watch it again.
The entire cast did a great job (particularly Wahlberg, whose performance really helps to "sell" the Ted character) and there are some interesting cameo appearances. The effects for Ted (the character, that is) are good enough that you accept the character for what it is and just "go with it". And the humor is definitely not for kids, but I was expecting it to be raunchier than it is.
I don't want to say too much (spoilers), but my main problem is the sub-plot involving Giovanni Ribisi's character. It felt forced and disconnected from the rest of the movie, as though it was added simply to push the movie's run time over the 90-minute mark. And I'm not sure anyone told Ribisi it was a comedy.
Bottom line, I think people who enjoy Family Guy will like the movie, and those who don't, won't.