Ça va sans dire, rhizome can't be the "essence" or "center" of anything because it's by definition a network without centers. As A Thousand Plateaus itself says, you can never posit any dualism, not even rhizome vs arborscence -- every tree has its rhizomatic effluences, every rhizome its arborescent tendencies.
I realize this entry is about "Mille Plateaux" the record label and the book needs an entry of its own, under its english title. But the indeterminacy of the political content of deleuzian thought bears repeating every time artists try to appropriate it. Even in his posthumous video interview, the "Abecedaire", Deleuze reaffirms belonging to the "gauche" but proceeds to disavow ideas such as revolution, majority rule and on and on. "Of course all revolutions fail, was there ever anyone who really thought otherwise", says him in an involuntary burkean echo. At the end of the Gauche segment, he ends up sounding borderline libertarian. Rhizome isn't the only thing to grok about ATP; of major importance are stratification, Bodies without Organs, ritornello. What's more, it's at its most overtly political -- the "Treatise on Nomadology" -- that ATP can be read alternatively as a defense of wild-west chaotic markets if you want to force it that way.
I think the most concise distillation of what Deleuze did say about politics is in the "Abecedaire", the aforementioned posthumous interview. Speaking of joy, Deleuze echoes Nietzche saying it's the realization of potentials (puissances), and goes on to say that il n'y a pas des puissances méchantes -- there's no such thing as evil or mean-spirited potentials; a destructive hurricane is filled with joy in the realization of its potential. Power (pouvoir), on the other hand, is the ability to interfere with the realization of other people's potentials -- and thus dictators and hurricanes carry sad joy.
My own general impression from Difference and repetition, three different editions of ATP (portuguese translation, Brian Massumi english, original french) and the "Abecedaire" is that Gilles is admittedly and unabashedly bourgeois, and the political problem really is that not everyone enjoys the minimal income security to have time and energy to think and produce philosophical concepts, art, science. This is emphatically not the Deleuze-as-a-continuation-of-Foucault I keep seeing in art circles.