‘The question is, what will Putin want.’
I think the simple answer to this is, he’ll want to keep the Russian naval base at Tartus. It’s enormously strategically important, being Russia’s only permanent naval base in the Mediterranean, or indeed anywhere outside the former USSR.
I’d expect some deal whereby the ‘Free Syrian Army’ agreed to allow the base to remain in place (initially, at least) in return for the Russians agreeing to turn a blind eye to whatever Obama eventually decides to do in Syria.
Deja Vu all over again. That was the deal that was supposed to brokered last time, but just a day or two later one of the rebel groups stated they would not allow the base. The force driving this entire intervention is the House Saud. And they are not very happy with the Russians supporting the Shiites.