Came to this thread, pretty disappoint.
Graphics are nearly pointless to argue,
in general, increase in time = increase in graphics. NONE of the zeldas were mind-blowing with the graphics (plus, graphics are totally irrelevant next to gameplay)
Plot of all zelda games are pretty much not much better or worse than each other. MM was probably the most interesting/ original (and the gameplay style change mirrored that difference).
To me, gameplay is pretty much what it's all about. My favorite COMBAT system (just plain swordfighting) was WW, I felt that it flowed well, and while being a bit easy, was fun. Ocarina and MM were both great, no complaints. When the Wii came out, and then TP, the gameplay was just slightly ruined for me. Instead of inputting commands, I was now simply waving the wiimote back and forth arbitrarily in order to fight. (note: I also played TP on gamecube, the combat was much better, but it also suffered from losing an item slot [why not assign midna to the d-pad???]) Now, SS comes out. Now I feel that this thread has way more appreciation for SS than it should, which puts me in a bad place, but honestly I feel that SS just took a big **** on the combat system. Every goddamn enemy is built around the one fact that they made the sword direction sensitive. It's like nintendo was just trying to justify buying the wii-motion plus. MAYBE if the controls were about three times more accurate, would I not have a problem with this extremely gimmicky design. On top of that, there is literally NOTHING challeging about SS except for the fact that you'll get punished by making the wrong sword swipe (which, most of the time was NOT the way I swiped it). My god, the gossip stone if a freaking guidebook. The poor controls are the only reason this game is even remotely difficult, which in my opinion, it still isn't. Sure water temple on Oot was hard as hell, but it was also satisfying as hell and worked your brain. In OoT and MM, there were always more ways to optimize what you were doing, plenty of side bonuses, and always something new to do. Combine this with all of the glitches and you essentially have a game with everlasting replay value.
Yes, 'most' of each zelda game is generally similar, but they've hit a wall when I can predict the exact order of plot and how they will implement each new dungeon item, as well as instantly solve any puzzle. The only thing SS implemented that was actually innovative for the series was
-the rpg style upgrades (which, let's face it, is not actually innovative at all [but they get points for effort, it wasn't awful])
-certain technical aspects (skyward strike, moving time crystals, etc., but even these are just extensions of used ideas)
-the characters
I have replayed Oot, MM, and WW probably 3 times each, and they're still fun. I've replayed TP once, and it was meh. Favorite part about that was sword techniques and new items (and only on the GC). SS I will probably replay someday, but it's just so cookie-cutter instructional (and again, based entirely off of inaccurate controls) that I didn't enjoy it nearly as much as the others.
And in case you were wondering,
Oot=MM > WW > TP > SS
All of them are good.
But let's face it, if zelda didn't exist until TP/SS, it would never have such critical acclaim.