Well i believe we are getting new characters because in the video I didn't recognize anyone of the stewards and one looked like he was wearing new armor? I havn't seen the kind he was wearing...

You get a brand new 4E 201 carriage that runs at a smooth 1 horsepower.

OK...

-New Women/Men to marry - Doubtful. But you can add a steward or bard to your household.
-More Orphans (and is there a limit on adoptions?) - At least one new one. Scuttlebutt says two is the max, but we can't be certain.
-More companions - Doubtful, but you can repurpose existing ones.
-Will the rest of Skyrim even know of your new house? Maybe a few guard quips here and there.
-Will We we be able to fortify our homes? A military outpost? Guards? Archery Towers? Traps? Don't know. It would be a good idea. It would be cool if you could recruit a few companions, Blade-style, for home defense.
-Can we open a storefront based out of homes (like almost all shops in Skyrim)? I expect your spouse will continue to operate his/her store.
-Will any new quest be attached to this DLC? Who knows?
-Any new enemies to encounter? (doubt it) As do I.
-Any new weapons? Doubtful, but we can hope..
-Can any part of the house be below ground? Yes, I think wine cellars or some such thing were mentioned.
If anyone can give a link to find what content will come with DLC please share!

Glad to. http://www.gamesas.com/topic/1407775-skyrim-team-diary-6-hearthfire/

It's funny how many posts were made before I finally got some reasonable answers.

You kno, when I first heard about this add-on I admit I was skeptical. Starting to lose my faith in beth. Making TES into the sims or some [censored]. But if its only 5 dollars hell, might buy it myself. Even though I don't like where this is heading, it shows beth IS paying attention to what the fans want.

Dayummm, that's one pimpin carriage.