It is a decent poll result for Obama, but I'm a bit confused why this is great news. +4 isn't an insurmountable lead at all, and if Ohio goes toss up the math gets a lot easier for Romney.
+4 at this moment in the polls in the most important swing state is an excellent place to be. Again, even the size of the bounce Romney seems to have already gotten is unprecedented in many respects. If he were to get another equally sized bounce before November he STILL wouldn't be leading in Ohio.
edit: Everybody already made this point, FINE, I was busy in another window.