Until now, I don't think it has changed a lot. However, we've heard a lot of declarations from the Iranian representatives that in the case where Syria will be targeted by the international community or by international forces, it will enter into war. It's a declaration of the Iranians much more than the analysis that we have.
However, the only reason, and why it's important, for Iran today to have its fighters, Hezbollah, in Syria is that the Syrian regime is a must for the Iranian-Hezbollah link. It is of real importance in the matter of arms, money, and everything in order to keep the link.