@Lexurite:
^Okay but Momo and Kin'emon have been around ever since PH and they never took off in terms of popularity
True, but their panel time has been pretty minimal in comparison to Law.
There are still so many mysteries surrounding Kin and Momo, while Law's past and motivations have been pretty thoroughly fleshed out over the last few years.
Add that to Law's more typical cool guy design, and his (while hax at times) incredible DF powers and it's pretty understandable why Law is not only so popular, but also miles ahead of characters like Kin and Momo.
@Lexurite:
. It's baffling to me how he just beat out Zoro in terms of popularity. It is because he's cool looking and aloof?
I'd say it's actually the opposite.
It's only been after Law's tragic past and emotional side have been explored that he's become this popular.
Nobody is going to appeal to cool looking stoic character fans more than Zoro, that's just how it is.
Zoro has been becoming more and more bland as time has gone on, while Law has grown as a character and as a result gained a lot of fans.