They are aware of that and are planning changes including moving to Compiz
from Mutter. Unity has been a work in progress, but this announcement should
give it some impetus and breath some life into Compiz. I am not sure how
this will affect users who do not have compositing. The last article is
worth a read.

www.jonobacon.org/.../
smspillaz.wordpress.com/.../
www.webupd8.org/.../...mpiz-instead-of-mutter.html
www.osnews.com/.../Ubuntu_To_Switch_to_Unity_on_Desktop