I didn't have a problem killing dudes in the beta, and the weapons had a lot more, I don't know, punch to them. I always considered the weapons in Uncharted to feel flimsy for some reason. It's been a while since I played it so it's hard to compare, though.
Visuals were immaculate, in the co-op mode. Sharp everything, and I don't recall experience much in ways of tearing or frame drops. Didn't spend enough time with MP to judge it either way, but it was certainly detailed enough. For reference, the monastery exterior and interior were the only bits in Uncharted to really impress me, so hey.
Oh yeah, and fuck MAG. Finally completed the update, created my character (the presentation is ridiculously slick), and was greeted to servers closing down for the night. 8-12 is really the shittiest time they could have picked, but I suspect I'm in the minority there.