I think that the things that worked well for extremely good games in the past are the same things that work extremely well for good games in the present (and probably future)... :
1.
Good Storyline (abosolute must-have)
2. Differentiated, yet balanced gameplay
3. Very few bugs/stable programming
4. Fun to play
5. Has some flexibility (and re-playability) for own style of play to emerge
Now, is it bad for a new game to look like it came out 5 years ago? Of course. But to me, that does NOT factor into if the game is good or not. Additionally, games should be trying to bring in new ideas or concepts, but these 5 criteria have been the same way, I would say, since Pong.
But seriously, look at what are considered "great/tiemless" games... Starcraft, Half-Life (and 2), Warcraft, WoW, FEAR, Civilization series, SimCity series, Diablo series, C&C the list goes on. But when you break it down, these 5 things every one of them has in common.