It seems I wrote my Tron Legacy review just in time!
Here's Tron: Uprising preview trailer from the ComicCon, released just now officially.
What a coincidence!
Yes it will feature a unique mixture of 2D (characters) and 3D (The Grid).
It will follow Beck (voiced by Elijah Wood), the program who leads the uprising on The Grid. The whole thing takes place right before the film Tron: Legacy.
Also lending their voices to this series are Lance Henriksen, Mandy Moore, Bruce Boxleitner and Paul Reubens.
The 10-part micro series will air on Disney XD this fall, and then pick up for a regular spot in the summer of 2012.