Considering that anyone and everyone can die during the final mission, I'm really interested to see how Bioware plans to include party members from Mass Effect 2. Just because it's possible to have the perfect ending where everyone survived, there's no guarantee that everyone who played and beat the game got, or even wanted, that ending (I personally have a perfect ending and an ending with 2 dead team mates just to see what happens). How does Bioware account for the dozens of survivor variations? The easiest thing to do would be to retcon the ending in some way and definitively say that certain people survived.
I personally don't want another long game of recruitment, but I imagine there's going to have to be some of that in ME3. Like others have already said, part of the game will probably have Shepard recruiting an army to fight the Reapers, but I hope that's not the main thrust of the game; that plot would be too similar to the plot of Dragon Age Origins in my opinion.
It did say a $20 gift card, you're right, it's applied to your Amazon account directly. I haven't seen one show up on mine yet, but I think it can take up to 10 business days if I remember from my experience with the Heavy Rain pre-order bonus.