Since Syria refused to sign the CWC (because Israel had WMDs) it is really impossible to know what kind of weapons Syria might have, but I think that it is not unreasonable to assume that the Syrian chemical weapons program would be more or less on par with what Iraq had under Saddam Hussein: Sarin, Tabun, VX, and mustard gas combined with many possible delivery systems. If true, this is all very bad news, not because Assad is about to gas his own population, but because of the fantastic false flag potential such a wide variety of weapons creates.
First, let me immediately dismiss the likelihood of the use of chemical weapons by government forces on the insurgency. With the possible exception of chemical hand grenades, I don't see how the government forces could use their chemical weapons against an urban insurgency. Besides, chemical weapons are inherently difficult to use, and it is impossible to conceal the fact that they were engaged. Since Assad is quite aware of the current propaganda and since he shows no signs of being insane, I would consider the possibility of the regime using chemical weapons as pretty much non-existent.
But the crazed Jihadis? Oh yes, these guys are totally capable of using such weapons, not only against the Syrian government forces, but also against the general population or even their own forces and then lay the blame on Assad.
Furthermore, the US and NATO could easily arrange for another Markale or Racak false flag "massacre" and fire a few chemical rounds somewhere close to an al-Jazeera TV crew, say close to a group of refugees feeling to the Turkish border.
The US, NATO and Israel have a long and "distinguished" history of false flag operations - from Gladio, to the USS Liberty, to Operation Northwoods, to the USS Maine, to Markale to Racak to, of course, 9/11 and many others - and they have never had to pay a meaningful political price for engaging in such practices.
In the meantime, the Jihadis have resumed an all time favorite custom of theirs: beheading on video under the exalted screams of "Allahu Akbar".
They got away with such practices in Bosnia, but it did cost some a little bit of political embarrassment in Chechnia, in particular when they murdered some Anglos, of course, and now it is likely to again cause them only minor PR problems. All in all, the West has become used to being the patron for bloodthirsty psychopaths and while such videos might create some unease, it is not going to really influence anybody. Expect more of the same, only worse.