It appears as though boats work on land. You cannot climb blocks, but you can go down, and turn. Attempting to scale a single block will not work. Speed is unchanged from when in water, and so is friction (Meaning that it will still take time to come to a complete stop). I do not believe this was intentional, however, if I am mistaken, feel free to take down this report. Forgive me for the single screenshot, I cannot capture gifs or video.

I will gladly test other blocks (Meaning that I will see if the boat behaves in the same way on other blocks. So far, I'm seeing this happen on Podzol, Spruce Leaves, and Sand.)

Personally, my theory is that the boat is in fact confusing the ground for water, and as a result, is treating it like water.