Watch the Gypsy Rhythms: Introduction online guitar lesson by Reinier Voet from Gypsy Jazz Guitar Guidebook
In gypsy jazz, apart from being a good solo guitarist, you need to be a good rhythm guitar player. The rhythm guitarist makes the band swing and functions as the drummer in this style of jazz. You must stay in rhythm AND in the harmony, as you'll be playing the chords too. Your role is to be the backbone of the band.