Sonic x Shadow Generations is averaging a 80 on Metacritic right now, seems like the new Shadow levels are pretty good.
Will experience both Sonic Generations and Shadow Generations for the first time, I'm looking foward to it.
I'm currently playing Sonic CD via the Origins collection for the first time too and everything it does right it does another very wrong too, the game is purposedly designed to be as annoying and frustating as possible, looks amazing and having the different versions of the stages are cool but I can't believe some people think this is the best classic Sonic game... hopefully it gets a lot better when you already know it well but Sonic 1, 2 and 3 are a lot of levels above CD.