Seems that right after upgrading to Atahualpa 3.7.15, posts that had used SyntaxHighlighter 3.1.10 stopped showing any of the SyntaxHighlighter styling.

I have no idea how to debug this. Any suggestions?

Thanks!
Rob

After updating to 3.7.15 did you hit the green save button in the header, center, and footer sections of the theme options?

The highlighter works fine for me on Atahualpa 3.7.15.