I've never been on a US flight (in recent years) that went somewhere other than terminal 1. US' gates are in the "top" pier on the map you posted (where the two octagon shaped terminal ends are), with a couple more in the "hallway" before the terminal splits in two.

How far away is your flight date? With the US/AA merger I could see US flights eventually moving into terminal 2 (where AA is). You might want to keep an eye out for them moving.