FNS will probably have Song 4 u + some old track. However, it's been ballad central there so maybe she'll do how beautiful you are or something. I think her last one was SEASONS + Days? GORGEOUS. I don't think it will have anything to do with A CLASSICAL since the release will be in January and FNS is in the first week of December.
Recap of her FNS performances:
1999 - appears
2000 - M
2001 - Dearest
2002 - Voyage
2003 - No way to say
2004 - Moments
2005 - Pride <-- she looked awesome here
2006 - JEWEL <-- this was amazing
2007 - Together When...
2008 - SEASONS + Days
As for YouTube, remember the ayu-mi-x 7 discs? They all got their own crossfades of the CD contents.