I wish it didn't take them over a decade to finally do it, but Sega finally made a really good Sonic game again. The sections with old Sonic play exactly how you hoped they would, and the new Sonic sections play pretty damn well for the most part. While the levels are based on ones from older games, they didn't just rehash them in either 2d or 3d. They kept the iconic sections and general feel, but designed new levels around them. Through this, it manages to have more of its own identity than something like the New Super Mario Bros. games. On the negative side, some of the later 3d levels don't play that well, and the last couple of boss fights were annoying.