I'm usually very anxious when it comes to reading popular books, because they often can't live up to the hype for me, sadly Babel is one of them. 
I think it is a beautiful book, which is also very beautifully written. The ending gave my goosebumps all over my body. Babel tells a story I have not read like that before and was very unique.
The biggest flaw for me were the characters. I found them quite one dimensional. Changes happened way too abrupt for my liking. The story itself was predictable but I didn't mind that. 
It was still a great book but it simply did not captivate me like other books did.