I think I must be going soft in my old age, because The Help is the second book-to-movie adaptation I’ve seen recently and had no real complaints about. Of course there were the small changes that always come with such adaptations, little things left out to make the story shorter and easier to follow. But there were no major plot points that I felt should have been included and the feel of the book was preserved beautifully.
One major change I expected was the way in which the story was told, since in the book the story is mostly narrated by the characters. Fortunately, there actually was a lot of narration by the characters much of which came straight from the book. The dialogue was also very true to the original. In both cases, I really appreciated the direct use of quotes because the narration and the dialogue in the book were just so good!
The casting was also done very well.. Getting to see everyone from the book at least very close to how I pictured them was great. One of my favorites was actually Celia Foote, who’s personality came across clearly from our very first glimpse of her. And while there were a few characters whose appearance didn’t exactly match my mental image, their acting was always spot on. This is one case were the book was so good I was sure the movie wouldn’t live up to it, but they were actually very similar experiences. I think you could probably read and watch in either order without taking away from either. And I would definitely suggest doing both 🙂
See my review of the book here.
Doing Dewey 
I didn’t get a chance to read The Help before I watched the movie though I had planned to, I really liked the movie though
I’m glad you liked it any way 🙂 I’d say the book is probably still worth reading if you get a chance, but I definitely don’t think you missed anything by seeing the movie without having read the book.