First, let me say I'm no expert on Obama autographs. But having seen his sig on many occasions, I would definitely lean toward this being authentic. This is in line with many exemplars. Plus, most of the time, we see the more abbreviated version.
With this being more of a full sig, I think there is less likelihood of this being a forgery. The abbreviated version is much easier to forge I would say. I think it looks good, IMO.