What is the red white and blue suit shown in the Iron Man 3 Trailer?
If you zoom in on that image you can see that it has "Lt. Col. James Rhodes" stenciled on the chest plate.
So, although that does look like the Iron Patriot armor from the comics, I think it's just War Machine with a new paint job.
Original image source: First 'Iron Man 3' Poster and New Images Reveal Cool Armor and the Film's Villain
It is a reference to the Iron Patriot Armor -
"full battlesuit patterned after the heroic images of Captain America and Iron Man".
As shown by Bill the Lizard above, it's Lt Col James Rhodes driving the armor.