We're in open G tuning on this one, which is from low to high DGDGBD, tuning the strings to a G chord. The tuning really provides the sound of this tune, the open ringing strings really have their own timbre and also allow us to get some drone strings. Keith Richards has played exclusively in this tuning for the last 20 to 30 years. In fact, he's reworked his older tunes that were in standard tuning to open G. I would highly recommend checking out some Stones tunes to get into the sound of open G.
As cool as it is, there are a few "tricks" to the tuning that become fairly apparent once you learn a handful of Rolling Stones songs. The first one I'd check out is "Honky Tonk Woman," then dive into "Brown Sugar," "Start Me Up," "Tumblin' Dice" (capo the 4th fret) and the totally amazing and awesome "Can't You Hear Me Knocking." Basically learn all of Sticky Fingers and Exile On Main Street. That'll get you firmly into non-slide open G and you'll learn some of the best rock tunes ever. I know I've gotten off the Zeppelin track here, but pay close attention to Keith Richards rhythm guitar playing, it's so odd and cool.