Here is a list with all some of the new studios / teams that joined Microsoft. Which team / studio do you think has the best chance of creating the best gaming experience.

Microsoft Los Angeles

According to different job ads, Microsoft is looking for a variety of developers and movie makers to create a mix out of these two forms of entertainemt. The product should be highly cinematic. If it follows the TV model, episodic content like we have seen for The Walking Dead of Fable II is easily possible. They have a big focus on story telling and try to create something unique. This is an AAA core game and they hired a former CBS TV exec for it.

http://www.gamespot.com/news/microsoft-creating-franchise-that-blends-games-and-film-6401542
http://www.gamespot.com/news/microsoft-hires-former-cbs-tv-exec-6396737

Black Tusk Studios

Black Tusk Studios was founded as MS Vancouver 2 years ago. Since then they have been hiring and build up a whole new team. There are currently 55 developers working on a new AAA core game, but that number should be doubled through 2013 to over 100 developers. The studio manager is Mike Crump who worked for EA Vancouver as Senior Development Director for 6 years and worked on the Fight Night and Fifa games and he took a lot of different developerf from EA Vancouver with him. The lead designer of Crysis 2 joined the team as well. In an interview Mike Crump said they wanted to create "the next Halo" for Microsoft.

Lift London

Lift London is a newly founded studio by Microsoft. The team tries to develop games for the cloud. Yeah, we have heard this before, but this time it should be more than streaming your gaming content to your device. They try to create games that grow with the cloud. This was discussed with the cancelled Milo & Kate project at Lionhead, where Milo learns things by thousands of users teaching him things. Think about a growing A.I. that gathers information due to other people play the same game with a different technique. It is uncertain if they really do develop a cloud or just support other studios with this kind of cloud gaming. The idea behind it is awesome though.

Microsoft Redmond

This is more a newly founded Team for the Microsoft Studios than a studio by themselves, but it is very interesting to see what happened here. There is not much we know about this team, except some of the developers working on it, but that is enough to get hyped. MS hired one of the game desginers from Naughty Dog who worked on "Uncharted 3" and "The Last of US" plus some of the best developers from Irrational games, best known for BioShock 1 and the upcoming Bioshock Infinite. They secured the AI Lead developer, Senior Designer, Combat Design Director and the game producer of BioShock 1 and Infinite. The Game designer of Halo: CE and the Character Technical Director of Sucker Punch joins the team as well. Well, that does not sound too bad.

Microsoft Victoria

Microsoft Victoria is another studio in Canada that opened its doors recently. They started in late 2011 with the hiring process and are probably still building the whole team up or have just finished the process, because there are no job ads left for Victoria at the moment. The technical director of the studio is Chris Robertson, who worked at Radical Entertainment, known for Prototype, Black Box Games, known for Need for Speed and United Front Games, known for ModNation Racers. They expected to hire 50 - 60 developers in the first year. They are working on a core AAA game, but we haven't heard anything about it though.

Have never heard of either of those, but if I had to choose, then Redmond.

Of course you haven't heard of them they haven't created anything and just opened in the last couple of years.

Im most interested in Black Tusk as they are building "The next Halo" franchise for MS.

Its already confirmed to be a huge budget, AAA, new IP

Black Tusk for me as well for the same reasons BenVTrigger mentioned.

Black Tusk is the one to watch, I think. I just worry that its big project will be another sci-fi shooter.

I would have to go with Black Tusk but I will be watching what all of them are doing closely.

I didn't know about Redmond and LA studios. I'm not sure if there are actual game studios.

They are both game developing studios based on who they hire and if I am to believe Wikipedia. 

Which one is working on Avatar Kinect 2.

Well i'd hope for Black Tusk but i'd say Microsoft Redmond based on the talent they got.