I am to please
That button really just functions as a "go" command for whatever's in that url bar. It's actually pretty clever to have it also serve as the refresh, but it took me a sec to figure it out as well.
One thing I like about this is that it seems to be aimed at a more sophisticated user than some browsers/applications. It may take a moment to learn the ropes, but it's going to result in a much better experience.