Yup.  I heard the rumor earlier today but I wanted a wait a little to get a confirmation.  Cassad (whom I trust) has just confirmed: Russia has deployed S-400s in Syria:

S-400 in Khmeimim

S-400 at the Russian base of Khmeimim

The western “response”? Total panic:

Selection_073Good.

Let them panic.

The Saker

UPDATE: The Russians are now denying these reports.  I go with Cassad.