Jim notes that caution, and knocks the wattage of his grin down to a dull set phasers to stun. Everything about Bruce, from his body language on down to his verbal cues, is telling him that this guy's cautious with damned good reason to be so. He holds up a hand. "Just something I've been thinking about. Sorry, didn't mean to come on too strong. One of my best friends is big on the whole science frontier." And if Spock ever shows up, he will deny he said those words to hell and beyond.

There's probably something regarding the Prime Directive he should be concerned with, but hey-- Spock (the older one, the one he doesn't want to punch in the face every now and then) dumped an alternate future's worth of memories on him. The concern is there - changing the future by meddling with the past (and 2012 is way in the past) but he dismisses it. It's one of those bridges he'll cross if and when he comes to it, not before.

"2259. Name's Jim, Jim Kirk." He holds out a hand.