I'm glad the animators are making a point of prominently showing "that" thing that became (kind of) important in the current manga arc. I won't spoil, and it's mostly trivia anyway, but Oda must have told the animators about it. Neato.

I'll laugh and laugh when it becomes important and everybody's like "Huh, where did that come from", just like us manga readers did. (I am not trying to be a prophet (or tease much) -- it is all in good fun.)

Sorry, I guess this post is mostly contentless unless you read the manga and know what I am talking about. So, here are my opinions about this episode:

(1) cute mermaid.
(2) it's about time we see more stormy weather on the Grand Line, though currents that actively follow the ship are kind of gimmicky. The real scariness are currents that act unpredictably.
(3) Garp is always awesome, but they made Sengoku look like a weak tool in this episode.
(4) Is Mariejoa a sky island? I don't remember it looking like one during the Arabasta arc, but they might have Vearth on top of a cumuloregalis cloud (appropriate for the seat of world power)

(5) I think Zoro came to appreciate Luffy a lot more after the Kuma incident. Zoro is the only straw hat who realizes just how much pain Luffy goes through to protect his nakama. Of course, Zoro gladly returned the favor (which is pretty bad ass, too). Kuma was probably like "holy shit that is a big bubble of pain."