Yes bigdeal000 I agree its hard to predict things such as pairing in One piece when the manga is not about that. This is why I point out that I don't think we will see actual romance in the but we may see pairing at the end much like Dragon ball since both share similar attributes:
Stupid lead Character
Adventure and Action based
Time Skips etc
Oda I believe wants Luffy to look like this towards the end of ONe piece
http://www.mangahere.com/manga/one_p...c001.1/49.html
Its from his one shot Romance Dawn.
I really think we will see a more mature Luffy the way we saw a mature Goku. For this reason I think its possible for Nami to like em after another time skip towards the end. As of now he is a kid but I really think after he matures a bit there will be a 1 sided love from Nami.