Digital Foundry takes a look at SmartGlass, the Wii U GamePad and the PS3/Vita connection.

http://www.gamesindustry.biz/article...-screen-gaming

Xbox 360 has no Bluetooth functionality, suggesting that SmartGlass would need to interface with the console over WiFi - this suggests some degree of latency that could limit some of its gaming potential.
Sony's pursuit of CrossPlay titles and its excellent LittleBigPlanet 2 PS3/Vita upgrade offers an interesting, if somewhat resource-intensive, take on second screen gaming.
Which leaves us with new Nintendo console, the star of the second screen movement. The principal difference here is that the tablet isn't just a value-added extra as it is with the Xbox 360 and PS3/Vita offerings - it's the core of the experience, with the most exciting, versatile technology. Hands-on with Wii U, we were drawn to the concepts Nintendo came up with and surprised by how robust the third party exclusives were. PS3/360 conversions with tablet functionality tagged on proved to be somewhat less compelling - and this is probably our principal worry with SmartGlass's gaming potential. If developers aren't going to make money with it (as they might from Vita double-dipping), and the applications are limited to value-added extras only, will SmartGlass attract the resources and ideas it needs to be successful?