I would place my bets on a story trailer, and we will see the protagonist.
If we look at gta 5, the first trailer showed off the open-world and all, similar to the rdr2 trailer. The second trailer delved into the lore and showed the characters iirc, and this trailer was almost 1 year after the first one, which would match with this red dead announcement. Also gta 5 gameplay trailer came like 3 months before the game came out, so I don't think this will have gameplay, cause we are at least 7 months out, probably even more.
Bet with Intrinsic:
The Switch will outsell 3DS (based on VGchartz numbers), according to me, while Intrinsic thinks the opposite will hold true. One month avatar control for the loser's avatar.