A new issue of Famitsu was released a couple weeks ago, and translations are beginning to surface. One user at NeoGAF translated the following details. It appears AC:3DS will be a major step for the franchise.
"- Can place a Reset Management Center. Mr. Resetti will appear after you have placed this on the map. - Return of Don Resetti. - Brewster's Coffee Shop is separate and you can build it. If you go there a lot you can begin a 'part-time job'. - Can drink coffee outside. - Can build two types of Police Stations. The police officer will vary by the type you choose. - New Villager: Hamsuke, a hamster, born May 30th. Brisk personality. - New Villager: Brittany, a pig, born November 14th. Mature personality. - New Villager: Anthony, a horse, born May 22. Smug Personality. - New Personality: Smug; talks indirectly but acts like a gentleman. Pure, so you can't hate them. - New Villager: Takoya, an octopus, born March 8th. Shaped like takoyaki. Carefree personality. - New Villager: Frappe, a penguin, born February 22nd, lively personality. - Lyle now works for the Happy Home Academy. - Picnics available (blanket, chairs, picnic basket) - New flowers. - Return of cherry blossoms. - Can eat ice-cream cones. - Seen planting the tree seen on the box art. This is your first act as Mayor. It will grow as your city does. - Can build camping grounds, bridges, wells, jungle gyms, benches, and those face-hole photograph things. - Receive donations from villagers and even other players to fund the building. - Clothing types: Tops, bottoms, dresses, shoes, socks, hats, accessories.
New Villager: Doremi, deer, born March 26 New Villager: Sunairu, gorilla, born December 5th New Villager: Hajime, elephant, born September 7th Flower Shop: Owned by Reiji, sells seeds for flowers, tree saplings, gardening tools, house plants. Open 10:00~8:00PM. He's a sloth, and lazy, so he may sometimes not be in the shop. Museum: Open 24 hours. Will have 'planned exhibitions' of items outside those which you give them. Also a Museum Shop run by Blather's little sister. Able Sisters: 8:00~9:00PM. Contains an accessory corner now. Nook Housing: 10:00~8:00PM, parts to decorate your house change every day. Run by Tom Nook. Speck Shop: Appears to be taking the place of Tom Nook's old shop, run by twin tanookis. Sells daily goods like cups for your house. Open 8AM~10PM, Starts of small and grows. Opening hours vary by type. Shank the Skunk runs a shoe store, Lisa the llama runs the recycle shop. Start the game off in a tent. Bunnie, Chevre, Peanut return as villagers."
Animal Crossing: The other oxygen.