Skylanders: Giants

Skylanders: Giants is a video game in the Skylanders series which is a spin-off of the Spyro series and is the direct-sequel to the 2011 game Skylanders: Spyro's Adventure. As the title suggests, it features larger Skylanders known as "Giants", along with other new gameplay mechanics.

Skylanders: Giants utilizes the first game's engine by building upon the fundamentals of the first game; merging a line of cross-platform toy figures with the video game world itself. The game will introduce eight new collectible figures that are more than twice the size of the original skylanders cast in both physical and virtual form. Their in-game powers and abilities reflect their colossal scale. It will also include a set of characters that feature new light technology integrated into the toys, allowing the figure to light up when near or on the "Portal of Power". These characters have additional in-game benefits as well. Players will also be able to import characters and their progress from the first game.

Source: Wikipedia, "Skylanders: Giants", available under the CC-BY-SA License.

Story
As a direct sequel the story picks up following on from Skylanders: Spyro's Adventure. Here is the very basic premise of the game as told by a press release:
Players will resume their role as a powerful Portal Master, who controls their a team of Skylanders, including Giants, mythical and powerful heroes that play a pivotal role in the quest to save the Skylands from Kaos, who is back with another plan to rule over Skylands. Players will navigate perilous lands, battle powerful enemies, collect treasures and solve interesting puzzles.
Joel Cohen and Alec Sokolow have returned to help write the story.
Characters
As well as the 32 Skylanders from the original game, Skylanders Giants introduces 16 brand new characters to play as. There will be eight giant Skylanders, at more than twice the size. In addition to those there will be eight brand new normal sized Skylanders to add to your collection.
And if that wasn't enough there will also be new versions of older characters, bringing the total number of new toys to over 20.
In the brand new Starter Pack you will get three Skylanders (a Giant, a new Skylander, and a returning Skylander), a Portal of Power, Trading Cards, a Poster, and the game. The Starter Pack will also be available without the Portal of Power for those who already have it.
To help differentiate between the old and new sets, the base of the Skylanders for Skylanders: Giants will be orange instead of the green currently seen on the Spyro's Adventure toys.
All of the new characters will be compatible with the online world of Skylanders: Spyro's Universe.

Portal of Power
The game will use the same Portal of Power as you used with Skylanders: Spyro's Adventure. You will be able to get a Starter Pack without the portal if you already have one. The Giants are sized so that you can still fit two of them on at the same time for co-op play.
Platforms
The game will appear on Xbox 360, PlayStation 3, Wii, Wii U, and 3DS as well as on mobile devices and the web. There will not be a PC version this time. I
Music
The theme music will again be by Academy Award Winning film composer Hans Zimmer and there will be a brand new score by returning composer, Lorne Balfe.
Toys R Us
Toys R Us will again have several Skylanders exclusives, all unknown at this point.