SPAN just keeps getting better.
 
New feature: RT Sigma analysis, which Aleksey describes thus:
"RT Sigma displays dispersion of the power spectrum. It is a kind of "dynamic range" display - the louder the frequency, the more dynamic it is."
I'll let you know what that means once I figure it out myself...looking at RT Sigma versus RT AVG they look pretty much the same to me.
 
Also new is a "spectrum offset" mode. That lets you either center or normalize the spectral display. This was the main missing feature that made me prefer MAnalyzer and MMultiAnalyzer over SPAN/SPAN Plus.
 
If you have SPAN Plus, the paid multi-track version, it will updated soon as well.
 
Here's the link: http://www.voxengo.com/product/span/?eref=ml
 

Thanks for the heads up.

Thank you @bitflipper - that sounds really interesting and valuable. I use SPAN all the time to get a handle on things.