*SPOILERS IF YOU CARE ABOUT THE AMOUNT OF DUNGEONS IN ZELDA GAMES!*

Currently A Link to the Past (3 Pendants, Hyrule Castle, 7 Dark World dungeons, and Ganon's Tower) and its sequel A Link Between Worlds (5 Hyrule dungeons and 7 Lorule Dungones) have the largest amount of dungeon in the series with 12! The second closest are Ocarina of Time (3 stones, 5 temples, and Ganon's Tower) and Twilight Princess (3 fused shadows, 4 Mirror shards, Palace of Twilight, and Hyrule Castle) tied with 9 dungeons. 

Seeing how huge the world in Zelda U is, is it possible for it to have the most dungeons in the Zelda series? And how many should the game have? 

Well, Zelda U looks hugee so hopefully, it will have the most amount of dungeons!

A huge dungeon with a couple sections each! . . . lol don't mind me, never even counted the dungeons in WWHD and MM3D :D.

Am I the only one who likes the Zelda games that have more of an emphasis on side quests (MM, WW) rather than a ton of dungeons (TP, OoT)? I really hope they're not just like "Oh shiz, we have to fill up all this empty space with something! 400 DUNGEONS EVERYWHERE GO" I'm not about that.

I expect a large number of mini dugeons (in the same vein as the ice caverns from OOT) and 6-7 main dungeons.

Oh, I don't hate dungeons at all. In fact, I love them. I just don't like when there are too many of them. I felt like Twilight Princess especially overdid it with the dungeons because not only were there 9 of them, they were all incredibly long and tedious. Games like Wind Waker, Majora's Mask and Skyward Sword really didn't bother me when it came to this because either a.) There weren't that many dungeons to begin with, or b.) The dungeons weren't overtly long. Hell, ALBW, even with all of its dungeons, didn't bother me because you could get through most of them in no time at all. 

But yeah, I love dungeons, I just don't want them to exist for the sake of existing. I want actual effort and flavor to be put in them. If it's in the style of ALBW (where you can do practically anything at any time), this should alleviate some of my concern.

I think it will start with 10 or so with DLC or Season pass type expansion 6 month or so later adding items, dungeons and storyline.

 MM was the most experimenal Zelda. The world was compressed and certainly felt like it had more puzzle, obstacles and more things to do including side quests outside of just dungeon crawling. The overworld map and Termina Fields were literally just 4 sections compared to Hyrule Fields which is just a big wasted space imo, yet both games had the same length.

I guess the OP thinks Zelda will get the Elders Scroll treatment because the world we saw in the demo was huge and he can only compare it to Skyrim as a point of reference. Zelda's each individual dungeon, pre-dungeon and side quest always had it's own theme and taste, and I expect them to keep that tradition and not turn it into an RPG. It'll probably have 10 more or less main dungeons but the overwold will also have sections with dungeon like aspects and a more emphasis on side quests.

I kind of sarcastically clicked infinite. Really though, I hope there are dungeons outside of the normal main dungeons. Ones where you get optional items, or save NPCs. Main dungeons, I honestly don't care. I hope they don't make so many that the games feels like it drags on for an incredibly long time. I'd rather have 9 to 12 dungeons that seem intricate to gaining items to beat Ganondorf, than 30 I have to beat for almost no freaking reason (as I said, unless they are optional).

I have the impression that Nintendo usually standardizes the number of dungeons at approx. 7-10, so I think we could expect somewhere in that range. 

I think that they're going to try to lengthen the game with more extensive sidequests, secrets hidden in the overworld, and real-time events, which is similar to what many open-world games usually do.

They did express interest at doing DLC, so if that becomes a thing, then they could add (I think) up to 2 extra dungeons, additional sidequests, story, etc.