I'm not sure it would be a good addition, but if it's optional and if it can make people happy, then no problem for me.
Another thing that could eventually make this CoverFlow superior to the Apple version would be 3D-displaying of the
real CD cases, not just the covers. I'm talking about the covers, but also the CD names on the case sides, and also the back covers if we decide to flip the CDs.
There is an excellent iTunes plugin (for Mac OS) called JewelCase that does something similar when the music is playing. Look here :
http://www.opticalalchemy.com/products.html
Graphically, this is the more realistic thing I've ever seen, period. Better than CoverFlow, better than anything.If someone manages to actually do quite the same with foobar, then I will be really, really happy.

For the back covers, JewelCase can do two different things to create them :
1/ It can take the front cover, zoom on it, flip it horizontally, and add the track names (see up here).
2/ It can take the front cover, make some kind of "blur" (like if the whole case was transparent), and add the track names (see below) :

Notice that the back cover is also used to create a background for the case sides. It even shows the now-playing track. And the used font (back covers and case side) is also beautiful, very readable IMHO. Last but not least, notice that the font color can be black or white. This could be selected automatically based on the back case's dominant color.
We could imagine a third possibility : show the real back cover when the jpg exists.
Of course it would be even better if we could choose, on a CD by CD basis, if we want the "real back cover", the "front cover zoom", or the "blur effect". That would be totally awesome.
What do you think guys ?