From what I've read, yes. There are three versions of Punch Out that appeared on the NES. One with Mike Tyson, one with the same final boss as the arcade version (Though it seems this version may have been a limited run, reward-type catridge for some NP related event), and a third, produced when Nintendo lost a lawsuit, or something of this nature, and had to forfeit the rights of Mike Tyson, so they made a few cosmetic changes, and renamed him Mr. Dream.
The version released today seems to be the third version. As far as I can tell, basically it's the same game as Punch Out featuring Mike Tyson, only a white dude named Mr. Dream is Mike Tyson.
I would rather fight Rocky, but I guess the devs knew that he'd be impossible to beat.