The digital effects on Bridges to make him look 30ish again are...well digital effects. Anyone can really tell that it doesn't quite look real. (notably in the upper lip and the corners of his eyes) Some people I talked to thought it was a bit distracting, but it only gave me a second's pause.
Nailed it right there. Hollywood still can't claim to have conquered the Uncanny Valley problem. I too noticed the upper lip and eyes thing, I'll forgive it thought because of the Lightcycle scene (wow, way to "update" it!) and of course Quorra and Gem...
This was my first 3D movie and after it went 3D (in the grid) it took a few minutes to get past the wow factor and settle in. Half way through the movie I kinda forgot it was in 3D and it just felt like it was more naturally immersive and not just "Wow!~ 3D for the sake of 3D - I'm coming right at your face!!!!!". They did really well in balancing things like focal point shifting and depth cues that felt real and not exaggerated.
As it seems to be shaping up around here, nice movie if you don't go in expecting Oscar work. Effects are great, acting, all right, story - stilted at times but easy to ignore for the eye candy.