This is an very good point. Actually the boat is moving forward, but since there are no points of reference (except the waves going in all crazy directions at the moment) and the fact that camera is moving along with the ship, it looks like the boat is at a stand still :-/ (I haven't re-implemented the space bar boost yet)
I will try to come up with ways to mitigate this problem. A few ideas are foam trailing the ship, other vessels, shooting targets, and islands. Other ideas that make it look like the ship is actually sailing are welcome :)
And I'm glad you liked the blog post. Thanks!