Miscellaneous thought/opinion:
My top fifty included both Gong Show and Love Connection, and I'd intended to include both Survivor and Amazing Race but both got brain-glitched off the final version of my list. Plus a series whose most famous run was outright rigged in Twenty One, a comedy vehicle for Groucho Marx (You Bet Your Life), and quite a few shows to have their first runs after 1995 (Debt, 5th Grader, Cash Cab, The Chase, the two reality competitions I'd intended to include but accidentally drafted out, Deal or No Deal, etc). The same list where I omitted forum favorite Whew - a very fun game whose evangelism for the show stops and starts within this community and that ultimately I get frustrated when I think about the format of. Blocking is at *such* a disproportionate advantage, and adding celebrities to the mix was not a good thing - almost never is. Is there a show? Is there a game involved, even a nominal one - whether that game involves trivia, or dating, or figuring out how much cocaine Chuck Barris could do between tapings? Congrats, it's a game show. That's my definition.
Because ultimately, a list like this is both wholly subjective - both open to broad/narrow determinations of "what is a game show" as well as the definitions of "greatness" (format? cultural relevance? personal enjoyment?) and additionally won't ever be a conclusive list, representing just a few dozen opinions within a walled garden.
Besides longevity, I think in deeper ways, the top three are what they are - and probably will be for a long time - because in so many ways they're the pinnacle of their respective types of shows. Jeopardy is the definitive quizzer for all but a select few, while you can make an argument for Password ultimately Pyramid has proven the more versatile, durable, and often enjoyable, and Price is Right is a sterling "game-as-variety-show", where there's a rotating mix of often wildly different segments, unified together by the emcee and show-as-structure, driven as much by the personalities of the players and the fun factor of the mini-games than the show as a whole.
Know what I'd really, genuinely love to see: Throw open greatness voting. Game show fans on Facebook, on Reddit, on show-specific boards like Golden Road and J! Board and Buy a Vowel. And if they can't think of fifty, then let them do twenty or twenty five. I'm genuinely interested to see what a greatest/favorite list looks like when left immune to twenty years of feedback loop and to folks who maybe don't have the entire history of the genre on VHS/DVD/HD. (The lengthiest and most sincere and most enjoyable real-world conversation I've ever had about a game show? Talking with a bunch of 35+ co-workers at a hotel about Remote Control. Who remembered it by name and would almost all - and we're crossing every demographic here - buy DVDs or iTunes releases if offered.)