I think the name is very fitting, and hints at an ancient "First Language" that named all continents - Edit 1
Before modification by Shannow at 07/04/2011 07:55:10 PM
This is pretty cool, but I must say I was hoping for rather more - maps showing a more significant part of "Essos" (which, I'm sorry, really isn't a great name, and stresses the lack of originality in "Westeros" as well).
Hence "Westeros" in the West, "Essos" in the east, "Sothoryos" in the South.
It is probably Valyrian, given that many of the Free Cities' names end in "os" as well, like Bravos, Pentos, Norvos, Tyrosh etc.
To me it fits together perfectly.