>Is airside transit available at YVR now?
No, it is no longer available post 9/11. You can read the procedure here:
http://yvr.ca/guide/around/connecting.asp?id=usa2int
Personally, I think this is dumb - The airport was specifically designed to support International -> USA travel without requiring Canada Customs and Immigrations, but bureaucrats will be bureaucrats - "Perception of safety and all that."
Cheers,
Geoff Glave
Vancouver