Well, nowadays Pokemon IS definitely going out there now, so I wouldn't throw a two-typed Gym completely down the drain. You know, considering they have 3 on 3 now, anything is possible, even though I somewhat doubt it for no good reason.
I have a lot of speculation and mind food towards a lot of this.
First of all the ying-yang thing, two black & white dragons, with two different types - Fire and Electric.
Does it scream Flint and Volkner? Yes.
Did it mention two jungle-like Pokemon with those types? Yes, Gorilla and Zebra.
There's definitely something important about those two types in this game, that we're going to see a lot of, so prepare yourself for Fire types and Electric types. I guess they just realized the lack of Fire Pokemon in the Sinnoh games, and the lack of Electric overall, considering there isn't a huge amount.
Also, another speculation I have is, Shimama, the Zebra, has some kind of relation to Luxray. They're both Electric Pokemon, share the same color-scheme and they're jungle animal type similar. Now whether that this relationship just means Luxray will also learn Wild Bolt, the new attack, they still have to have some kind of relationship.
Now moving towards what abilities the game will hold...
Considering that the game is uploadable onto a website held by the Pokemon website, obviously there's going to be a lot more Wi-Fi or internet abilities. Since there's places where you transform into your "avatar form", it just screams MMO capabilities. This ability, if true, would probably only consist when you're on the internet, not on the ds, where the random battles and whatnot exist. The DS connection would also be harder to hold all that information, the trainers, the Pokemon all on one go, but a decent internet connection could. This still lies in speculation for me.
Of course they'll stick to the 8 badges, elite four and one champion. Some of these types will be the same, and others will be different hopefully. I honestly don't mind what I'll see, but I'm just glad to see like super awesome roller coasters in a gym!
DISCUSS.