Card Hunter, from developers of BioShock, Captain Forever and Magic: The Gathering
What do game developers do when they get tired of making immersive, big budget first-person shooters? They make digital card games. Card Hunter is being developed by Blue Manchu Games, led by Jon Chey, Ken Levine's former producing partner at Looking Glass and Irrational Games. Jon previously worked on Thief, System Shock 2, and BioShock, and he's joined by Farbs (indie developer of the Captain Forever series), fellow Looking Glass vets Dorian Hart and Ben Lee, and the creator of Magic: The Gathering.
Right now, information about how the game plays is fairly thin on the ground, and the above trailer is described as "awesomely inaccurate." We do know that it'll be free to play, primarily singleplayer, and that they're striving to avoid anything that could be described as "pay to win". There's an ongoing Card Hunter blog, if you're thirsty for more.