Initially planned for release on PC & MAC, with the first episode expected in December 2010, the game is also planned for console release (presumably once the full season is complete).
From the official site (linked above) to quote:
Back to the Future
The landmark Back to the Future story continues in a completely new adventure starring Marty McFly and Doc Brown.
New Storyline with Marty and Doc. Featuring Michael J Fox and Christopher Lloyd likenesses, with Christopher Lloyd returning to voice Doc.
Thrilling new Back to the Future experience delivered in 5 parts. Released over 5 monthly episodes featuring incredible story twists, turns and cliffhangers!
Cinematic Adventure. Play as Marty McFly in an experience true to the films - with all the challenges, excitement and comedic stylings of a bona fide Back to the Future adventure.
• FREE Extra Bonus Game: Telltale's critically acclaimed Puzzle Agent - $9.95 value, available for download immediately after placing order.
• Insider Forum: We sign you up for special pre-release insider forum at Telltale site; chat with team creating the game throughout the process.
• Contribution to Michael J. Fox Foundation for Parkinson's Research. With series pre-order on PC and Mac, we will donate $1.00.
• Get free full season Collector's DVD. Available for order after series finale (you pay only for shipping and handling).
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