The best reason to see this is for its top-notch cast, although that's not to say it isn't a charmer. Unfortunately, it is cliched, but if you can get past that and simply enjoy it for the cast and setting (India!), you'll be fine. It's not a bad way to spend two hours, and I enjoyed it.
I saw this on a Thursday and was surprised by how packed the theater was. Most of them were older folks. They even clapped at the end of the movie, which...never happens when I'm at the movies.
Also, while the whole cast is good, I have to pay special attention to Judi Dench, Bill Nighy, and Maggie Smith. Those are my three favorites. I also feel I need to mention the cute, unexpected (to me) romance at the end. Awwww. I love happy endings!
My grade: B+