I don't remember which chapter this started in, but I've noticed that his smile is not as wide as usual. It's very different from his wide, rubber-skinned smile. Now it looks more like a girl's smile in One Piece.
I know it doesn't matter much but could there be another artist besides Oda who is working on One Piece? Or could this hint to something related to a change in his stretchiness or something?
I've also noticed that he looks younger than pre-timeskip. Both of these could simply be a change in Oda's art style though.
The last poster was shown in the manga too.