It may look like a Super Mario Galaxy Game, but it plays like a Sonic game.
http://www.nintendoworldreport.com/news/34617
An interview with Sonic Team head Takashi Iizuka, revealed many details on the development and components of the upcoming Blue Blur game.
Development of Sonic Lost World started before the team knew about the Wii U. They decided to make it a Nintendo exclusive because of how a second screen "gave us extra options and advantages". He also stated it would be an exclusive because "Wii U is where fans of action platform games are going to."
When it comes to actual gameplay, Sonic Lost World plays like a Sonic game according to Iizuka, though he understands how people draw similarities to Super Mario Galaxy because they both have "geometries with their own gravity." Wii U Pro Controller Support was also revealed to only be possible when used by a second player in multiplayer.
Sonic Lost World releases on October 13 on Wii U and 3DS.