Halo: The Master Chief Collection may aim to refresh gamers' memories about Master Chief in advance of Halo 5: Guardians, which was announced today. As such, it doesn't look like Halo 3: ODST and Halo: Reach will be included.
Microsoft has not confirmed the project. It's still unknown who's developing, the resolution and frame rate, or if the collection will release on other platforms.
As we learn more about Halo: The Master Chief Collection we'll be sure to let you know.
Check out Halo: Combat Evolved Anniversary for some idea of what what to expect graphically in the Master Chief Collection. Leah B. Jackson is both an Associate Editor at IGN and Corgi megafan, and not necessarily in that order. Follow her on Twitter and MyIGN!