Can I play a save from the non-GOTY edition of Red Dead Redemption in the GOTY edition?

Solution 1:

I have contacted Rockstar support and they have confirmed that save files are interchangeable between the standard edition and the Game of the year edition.

This means that any save created with the vanilla edition will load up no problem when you get the GOTY edition.

Solution 2:

The DLC in the GOTY edition does not affect the main story mode as the DLC is all multiplayer based except for Undead Nightmare, which is stand-alone. You can purchase the GOTY edition after playing the vanilla version and you save will be okay.