When the dust settles, it will be a 3-way contest: Royal, Delanoë, Aubry. The "Reconstructeurs"--M&M, Moscovici and Montebourg--seem to have been betrayed by Moscovici's rival among Strauss-Kahniens, Jean-Christophe Cambadélis. The Fabiusiens and local barons (Collomb, etc.) have been included in the mix. Behind the scenes, from a distance, DSK himself may have been pulling strings, if not pulling the rug out from under M&M.
So in the end it comes down to power politics: the very mediagenic Ségolène Royal vs. the very dapper Delanoë vs. the dogged bulldozer Aubry and her henchmen, Les Pieds Nickelés, blood still dripping from their respective daggers and wounds. Two "personalities" vs. an unappetizing ideological bouillabaisse.
"Bouillabaisse" is a fish stew that one heats until it boils, at which point the heat is lowered, baissé, whence the name. Will this apparent règlement du feu lower the heat within the PS? That remains to be seen. But bouillabaisse was once a staple of the poor whose status has gradually risen, even as its contents have often been altered and adulterated, so that now it can be found on the menus of the finest restaurants, often at an exorbitant price. A comparison with the PS suggests itself: once a party that purported to defend the poor, it's now an unpredictable mix of less than choice ingredients whose flavor and composition vary from day to day.
A leader will eventually be chosen and set afloat like a crouton upon this porridge of boiled marine life. Perhaps if a good enough ideological rouille can be concocted, it will even become edible. But I sense that many on the left are ready to give up on bouillabaisse altogether. Leave it to the tourists, willing to pay the price, and look for lighter, more modern, more eclectic fare elsewhere.