Watch the Up Rock online guitar lesson by Brad Carlton from Chord Studies: Rock and Pop Progressions Vol. 1
This progression has you playing an E chord in the 7th position. Using the "A form" barre chord allows you to then keep your first finger barred on the 7th fret and reach just a bit to cover the 5th string as well - giving you a D/E chord. This one is "pushed" timing wise, meaning it comes in on the and of 4. Use a little "dirt" on your sound for this one and it will rock!