I didn't know about the Dark Sentinel Prime toy before the movie came out. For me, the toy really did hide the betrayal very well and the tech specs portrays him as being an incredibly noble and heroic character; i.e. who Sentinel Prime was before aligning himself w/ Megatron. I didn't know he would go turncoat until I saw the film for the first time so it thankfully came as a complete surprise to me.

But different people have different levels of what they consider spoilers; for some people, simply knowing which characters will appear in a film are already considered spoilers. So I think asking whether or not the toys will release spoilers is rather subjective. Hopefully Hasbro won't release any story spoilers along with the toys as they did with TF Prime Bumblebee just before the airing of the last episode of TFP in the U.S. That was incredibly annoying.

I hope Generations doesn't take a back seat next year... Hasbro's only started to get good again with revitalising the Classicsverse line.