No word on whether or not the grooms will be wearing white or green at the wedding. I'm also pretty certain that Alan's engagement ring doesn't create emerald energy constructs.
All that aside, I'm a little nervous about Sam's future survival. Check out the Green Lantern image at this link. Green Lantern is looking awfully lethal to those standing around him. What do you wanna better that Sam and everyone else on that train are gonna get blitzed? Super heroes are too often spawned from tragedy.
I'm wishing for the best, but prepared for the worst. Good luck, Sam!
Updated Later on 06/06/12 To Add: I did some spoiler seeking this evening. My hunch appears to be correct. Sorry Sam...