I the past hour I have received two important and long awaited good news about the war in Syria:
1) al-Qusayr has been fully liberated by the government force, this is official and confirmed by the BBC.
2) Some Russian S-300 are already in Syria. This is, of course, not official at all, but I have it from a source I personally trust and who got it from a reliable person "with access".
Two points on the 2nd item: first, it remains unclear how many S-300 batteries are in Syria and, second, those who are currently in Syria remain under Russian control who have "conditioned their use or total control by Syria if and when
a major or all out attack on Syria by Israel or Nato".
I can see the logic for that: it would be to tell the Israelis "we (the Russians) control these missiles for the time being, so your airspace is not in danger (taking away one key Israeli excuse to attack Syria), but if you attack Syria, then we will hand them over the full system and you are on your own". If my guess is correct, then this is a very slick tactic as it minimizes the incentives for anybody to attack Syria, but it also maximizes the deterrent effect of these systems.
Again, this is my personal speculation based on totally unofficial information passed to my by a personal contact.
Caveat emptor!
The Saker