So, the other day we were discussing the latest Zinn tech article on Velonews (Feb. 19) and the inaccurate statement that SRAM 10sp cassettes won't work on 10sp Shimano hubs (as I am currently running SRAM cassettes on all my Shimano road wheels - 11x28 Baby!). Turns out it's only the Dura Ace 7800 hubs that are incompatible. Cyclistrick seemed pretty fired up. Now, there's a letter addressing the topic printed in the latest edition, sounding suspiciously of Cyclistrick's "official" tone and signed "Rick".
Your answer to Brian about SRAM cassette compatibility is confusing and correct in part, only. You state "Shimano 10-speed freehub bodies, however, are aluminum and have taller, deeper splines," which is true of the FH-7800 and compatible Dura-Ace level hubs, the only hubsets marketed by Shimano that work with matching Dura-Ace compatible 10-speed cassettes, only.
Shimano sells other hubs that are marketed and sold for use with 10-speed cassettes including the FH-6600 and FH-5500 hubs and compatible wheelsets. Of course these hubs work with 8- and 9-speed cassettes, too, which the FH-7800 hub does not. Thus the SRAM OG-1070 cassettes that Brian asks about work on most of the 10-speed groups and wheels sold by Shimano, the same as most of Shimano's own 10-speed cassettes such as the CS-6600 and CS-5600 series. The only quirk again is the 7800 series, with the higher spines you mention, which is an outlier with limited compatibility even in Shimano's own lineup of componentry. The limited options and compatibility is the reason that myself, and a lot of other riders, have avoided the 7800 level hubset.