And here I am, rolling up like a bad penny....
I think the main difference between the new American Standards and the previous American Series is that the bridge now has vintage-style bent steel saddles, rather than the "powdered" steel block-shaped saddles which have been used for the last 20-odd years. The tremolo bridge still has two fulcrum points rather than the vintage-style six screws, though.
So it's still a "modern" Strat, but supposedly with a slightly more "vintage" tone.
Apart from that, I don't know if there are any differences. They might have tweaked the pickups a bit and they've probably changed the colour range like they do every few years.