The song fits the album perfect conceptually. The album is called RECOVERY and this song has a good uplifting vibe to it, so logically it would be the first single. It probably isn't the best song on the album, but it's a solid single to put out given the direction he decided to take with the album.
I agree with the Kris about the flow, though.. By no means is it bad, or below average like some of what these other dudes are saying.. but I felt that some parts were flawed or out of place.. especially around the 2:50 mark.
The singing on the hook was pretty decent.. I think he did a good job singing.. It's genuine and original.. It would have been mad corny to put another artist on a song that's so personal to him.
Overall, I think it's a solid single to put out and I'm looking forward to the album.