Regarding WMA10

Hi All,
      I am a newcomer in the digital audio area & previously I worked in
Video Decoders. I have embarked on my first project of WMA10(Windows media
audio 10).
I had the reference codes & specifications for WMA9 & WMA10. Basically I
need to find the difference between these two versions & then start the
coding of difference on processor which I had the assembly language code
for WMA9.
I know the major difference between these two is Low bitrate support for
WMA10. There might be so many differences in terms of compression,
enhancements, quality etc...
I am trying to findout differences but it would be really helpful if
anyone let me know the exact differences or little difference interms of
functions.
Any other suggestions about WMA10 would be really appreciated.
I am a newcomer in this area so I am very much open for small comments
also.

Thanks & Regards
Raja