When I went to a Malankara Syriac Orthodox Church a few months back, I was asking the priest about the liturgy. He said that the Syriac form of the Liturgy of Saint James has changed significantly over the centuries, and that many changes/additions/subtractions have been made. He didn't really say anything about the Byzantine version though, but I can only assume that means the Byzantine one is the earlier version of the two.
In the Eastern Orthodox church, the most common liturgy is that of St. John's. However the St. Basil liturgy is prayed twice a year and St. James is done once a year (depending on certain factors).
Wait.........At my church(OCA), we do Saint Basil's liturgy every Sunday of Lent, Nativity, Theophany, and the Feast Day of Saint Basil. Is it different in the Greek Orthodox practice??