Even if this isn't what GF has in mind for their 'big announcement', it still doesn't hurt to speculate about the next gen. I know about the rumors that have been going around of Serebii and Bulbapedia's forums about gen 6, but those rumors are probably fake.
Do you want a new type? Do you want this gen to feel like gen 2 was to gen 1 except for gen 5 or do you want a fresh new start? How would you like the graphics to look like? Is there a specific type combination/ type of Pokémon you want to see? Please discuss all of your opinions below!

Starting with Gen II, we've already had an expansion (GSC), an incomplete expansion (RSE), a remake (FrLg), another expansion (DPPt), another remake (HgSs), a reboot (BW), and a sequel (BW2). Gen VI will most likely have to be an expansion rather than a reboot, or it will feel like a repeat of Gen I and Gen V.

As for actual Pokémon:

• Three-stage Grass/Fire/Water starter trio. It seems standard at this point.
• New evolutions and babies of old Pokémon.
• Two legendary trios, one involving mascots and one involving non-über legends.
• New abilities and moves.
• Changed movesets.
• Stuff purposely left out to be included in the revised version(s). Current favorites are the tutors, ability to catch more Pokémon, battling complex, and possibly more in-game triple/rotation battles.
• A transfer utility.

I would expect probably a new type as a new one has not been added in God knows how long. I would also hope for a feature in which you could visit old regions and also to catch old Pokemon from the old games. I think this is a big ask but maybe some sort of Co-op feature could be implemented somewhere.

Aside from the obvious things they add in each generation-

-I would enjoy a new type of sorts. I don't know what they could come up with, but hey, they have Rock and Ground, Ice and Water. They can come up with something.
-The good stuff that was cut out, like berry planting, Game Corner (This is hard, but there's gotta be SOME replacement), Safari Zone, and the ability to re-challenge any trainer with an item. The exclusion of these in 5th Gen confused and annoyed me.
-Optional slower speed for the bike. It's impossible to get into doorways with twitchy thumb movement.
-A BIGGER region that balances land, ocean, desert, and mountain/cave.
-More IR abilities. And with that, something much cooler to do on the bottom screen.
-No more Flash.

It's not much I'm asking.

I hate to differ, but I would absolutely hate a new type. It would disrupt EVERYTHING. And plus, they're probably going to come up with some cliche Light Type or something. However, new pokemon with new type combinations would be nice; i.e: Ghost + Psychic (Surprised there isn't one yet). and agreed with Cat AND Plusleplusminun's posts. I would hate another Fire/Fighting starter. However Cat, what does a Reboot game mean?

The only thing I am hopeful for in Gen 6 so far is a new eeveelution(s).

did anyone get what the trivia meant. they kept tweeting and reminding everyone of the 8th of January. the number of eeveelution are 7. if they add a new one it will be 8. get it? 8th and January will be the 8th eeveelution! then the official game names will probably be announced!... Maybe

Somebodys theory

I've always wanted these sort of things in Gen 6. Considering how there's even a countdown for the special news tomorrow, it might be the announcement for Gen 6. Considering how all even-numbered generations focus more on evolutions/pre evolutions from past generations, this is what I think will happen.

Stuff I'd like to see:
-New evolutions and pre evolutions (Maybe one for Farfetch'd hopefully? <:] )
-New TMs and moves.
-New kinds of Pokeballs.
-Addition of the rumored "Light" type to complement Dark types.
-Unique type combinations like Psychic/Electric or Ice/Steel.
-New abilities
-Dark type Pokemon Gym! We don't have one of those yet!
-A Fire starter whose final evolution is not Fire/Fighting. Too many are Fire/Fighting >_>
-Challenge mode available at the start of the game.
-Return of the Pokeradar.
-Fixing the GTS to stop people from asking for Level 9 or under Zekrom!
-Shaking and Double Grass just like in 5th Gen.
-No more Pokemon Musical.
-Trainer/sprite customization just like in PBR.
-The feature allowing Pokemon to follow you around from HG/SS

I don't know if this has been mentioned yet, but...

BRING BACK MY BATTLE FRONTIER.

The "Battle Subway" just isn't as good...

Looks pretty obvious that X and Y are Generation VI.

I actually noticed something about the starters, each them represents different times.

Froakie represents the original starters as in being amphibious like the original trio.

Chespin represents the future of starters as in pokemon that more creative in design with a spring of generic cuteness.

Fenniken represents the present, being a generic "cute" animal that appears in all of the games.

Ok I know that X and Y were officially announced today. From the looks of it, the new region looks like it's based off of France. There's an area that has a tower that resembles the Eiffel Tower and I think in one place I saw a character that looked like a European guard. I like Chespin and Fenneckin, but I don't like Froakie as much, but my opinion could be completely different once these games come out. It really looks like GF is putting in an immense amount of effort into these games. I can't wait to see more!

I bet that Wynaut will be exclusive in Y and Xatu in X.
Or Yanma for Y.

It's only been 16 hours and people have already started making fanmade themes about Pokemon X and Y. This one caught my attention about 5 minutes ago.

I can't believe there was a lot of evidence for new eeveelutions yet they weren't even in the trailer for X and Y. There's still a real good chance though. Coro Coro has been released and the new eeveelutions haven't been revealed, but I'm pretty sure they'll be reveled either in Coro-Coro next month or in the future, on Pokémon Smash, or in the games when they're released.