Just so you know . . . favorite threads change all the time. I remember back when a thread I started was one of the most talked about threads on the site. Some people fade away and a new crowd comes in and does the same thing. I don't know if all these threads you listed are recent threads or if some of them go way back in DGCR history, but it would be interesting if something like this was done from the beginning, like the top 25 threads of each year. Then put themhead to head with the winners becoming hall of fame. It's too late to go back and start over, but I suppose we can go from here forward, but if it was up to me, it would be a calender year basis. Maybe if a thread is nominated you use its inital posted date as the year of its nomination.
Maybe I am making this too hard. I vote this thread as my favorite thread of all time!