Of the three, I still like the B&W best. It has such a sweet softness to it. But the color saturation in the third is fun too. It reminds me of the classic print photos in everyone's childhood albums.
Foxor's suggestion about adding back in just a little of the original photo's color reminded me of this thread I read recently. There are really nice instructions in it about how to selectively add color.
My before and after [selective colour]