but that's a re-emergence of the "powers" in my view.

Oh, I agree, but it was the fact that Sam didn't suddenly use them to save Dean at the last minute that made me happy.

what is the extent of Sam's power and what will be the trigger that brings him into his own

I've been thinking the same thing! Will it just come naturally to him now, no "trigger" required since he used them, apparently unconsciously, to defend himself against Lilith? He's already "online" now?

a reflexive reaction, not even a defensive one.

Yeah, it seemed like that to me, too. Something inside him turned itself on when Lilith tried to zap him.

How will Sam get the knowledge and training to use his power to defeat Lilith and either bring Dean back, or get Lilith to

That's a really good question!

will Bobby be his "guide"

PLEASE, PLEASE! I love Bobby to death and the boys need someone like him in their lives.

And will next season's opener jump back into the story immediately where we left off? (I hope so.)

Even though I don't want it, something tells me it won't pick up right from there, but maybe the next day or so, kinda like when Sam "died".

I don't think Sam's power is buried any longer ... it is definitely awake and we saw him use it.

Nope, it's back and I'm looking forward to seeing what he does with it next year. :-)