Very nice pic. I see the Love Hina drawing style.
Some constructive criticism:
1] The eyes. As someone stated above, there is a bit too much empty space. If you made them closer or added a nose, it would be fine.
2] The "claws." If she were a bit more demonic [ie Morrigan], they would work perfectly. However, she's too happy for them.
3] The ears. Those are the smallest elven ears I have ever seen. Most anime drawings of elves capitalize on this feature. Below is an example.
http://server6.uploadit.org/files/sladextekno-Elf.jpg [is it against forums rules to post examples?]
For other good pointers on elven ears, try looking up a few pics of Deedlit from Record of Lodoss war. They are actually quite easy.