Alto's Odyssey is set for release sometime this year, and it looks like we're trading in the snowy peaks of Alto's Adventure for sandy ones in Odyssey.  There was a Youtube interview from E3 that Kotaku wrote about:

"Eli Cymet, lead producer for development team Built By Snowman, talked with Gameslice host Geoff Keighley about Alto’s Odyssey yesterday at E3, showing off some of the game’s new moves. Wall rides and dynamic obstacles add some upward motion to the downhill boarding game without adding any control complexity—it’s still a simple one-finger game."