Well, I went because my friends wanted to see it. And I gave it a 9 because I thought it was surprisingly good. It's not intense, it's not fast-paced, it's not a mind-bender. It's just a fun thing to watch. Diane Keaton is energetic and so much fun - and I promise you that by the end of the movie, she'll have (in some way or another) reminded you of your own mother. And Mandy Moore is very good as the quirky daughter who is, in reality, very much like her mother. It's just a sweet tale - most likely for women only - that reminds girls and their mothers that they're not alone in the battles. (Though viewers be warned - there's a little sexual content. And a little more conversation about sexual content...)
There's nothing terribly unique about it, but the writing is good and the plot is entertaining. There aren't going to be any surprises, it's just entertaining, lively, and very sweet.