Thanks, everyone! I'll write up a small label to attach to the quilt with pretty basic info, but when I give it to my parent's, I'll probably let them try to guess what each block could stand for, and who it represents (mom, dad, or both). This gives them more time to look at it and stuff while I'm there (and maybe my sister, SIL lives too far away). They had their 50th anniversary last year, but we hadn't really planned anything. We're pretty low-key, my sister made them a cake and we had dinner with those of us nearby.
The plan is to give it to them for Christmas. We'll see who all can make it to dinner, and then possibly break tradition and have them open it after that. If I can't get it done in time, they'll receive it "in progress" and I'll take it back to finish it (as long as it's not stuck on the frame or something). Hopefully it is finished well before then though! I don't want to wait any longer (already missed one Christmas), as my dad hasn't been in the greatest health. Too many scares over the last couple years.
I'm not sure if my son will have children, but if not, it will probably go to my niece. Hopefully not for many, many years to come though!