This is the first novel by Adichie that I have read. I think I have read one of her short stories (and liked it too: it is about growing up in a university campus, if I remember correct).
This is a very nice novel. Part 7 is the one I liked the best. The ending is not satisfactory. I also felt that the sections with Ifemelu as the narrator are much better written than those where Obinze is the narrator. I did find the novel sagging a bit somewhere in the middle.
… Americanah, which is as capacious, absorbing and original a novel as you will read this year.
I agree; very, very strongly recommended (and there is an Indian edition for about Rs. 400/-). Have fun!