[Brian]

I remember back in the pre-release test program, we asked folks to enable the column you're seeing to diagnose some sorting problems. If you weren't in the pre-release test program, though, I'm not sure how it got enabled.

In any case, if you quit OmniFocus, then enter the following command into a Terminal window - paste the command in, then hit return - the column should be gone when you restart OmniFocus.

The command you want is:
defaults remove com.omnigroup.OmniFocus ShowRankColumn