Pretty much what Shaddy said when it comes to updates. I guess someone could ask Mefiresu on the progress, since he's one of the people responsible for the project (Gistix passed this project onto him), but I wouldn't really expect anything at least till this year's SAGE.
Also love how some people here think it'll be a 1:1 recreation in movement/physics, when in both Kingdom Valley demo and Dusty Desert demo Sonic has much more weight to him (granted, I haven't played the original 06, but from the gameplay vids all characters look to be really twitchy and have barely any weight to any sort of movement). Not mentioning the fact that this was the first concern they said they're trying to address when they showcased(?) the test level.
I for one am looking forward to this endeavour, but I don't really expect it to be fully developed till, like, 2020-s, if at all.