I actually expected it to be overturned until the view from the back corner of the endzone was shown. I don't think it would've been reversed to a TD if it hadn't been called one, either.
Bryant had 3 feet land in the endzone - left, right, and left again. He definitely didn't control it when his first left foot came down, but it does look like by the time his right foot comes up, he already has it pinned against his hamstring. Does that foot count? It apparently does because he never loses control of it when his left foot lands or during the flip, and he gets up with complete control of the ball too. And even if he didn't, it was close enough that it's far from indisputable evidence to overturn the TD call.
Of course the ball moves because it's pinned to his leg, which is moving. That's not a bobble, he wasn't trying to adjust the ball. He never loses control of the ball at all, which is probably why there are very, very few people who've said it wasn't a catch. Some will, and that's OK, because some don't think he had it pinned to his right leg soon enough.