It looks like I'm locked into outputting with WMA 10 Pro. I spoke with the account exec at the ad agency and she didn't really know why the client wants version 10 vs. 9, she just said that's what they need.
Unlikely that they would know any different, but this is for our largest client, so I'll make sure I get them what they need whatever it takes.
Our animators dual boot their Macs, so while one was at lunch I downloaded the WME to check it out. It looks like it gives me enough options, but I didn't see the WMA 10 Pro as an option. He came back before I could check for WMP updates, but am I correct in assuming that 10 Pro was absent only because of a needed update? I would have that downloading the latest WME would give me up-to-date codecs.
-Andrew Saliga
Steelehouse Productions
http://www.steelehouse.com (undergoing a much-needed redesign)
http://www.vimeo.com/steelehouse