Souped-up Generations? Think about it. I know the guy said it wasn't a sequel, but come on. They're reusing old levels. And old villains! And it has all the protagonists together unlike Unleashed, Colors and Lost World. And Classic Sonic...
I think Forces is basically souped-up Generations. Though, to be fair, I think Forces is releasing on a better set of consoles than Generations. Every gamer gets Forces. But only certain gamers had to choose between Colors and Generations.