Interesting article on Sun's collaboration with Intel to improve performance
By Gerry Haskins on Mar 26, 2010
This isn't specifically to do with patching, but here's an interesting article from Intel detailing some of the work Intel and Sun have been doing to maximize Solaris performance on "Nehalem" Xeon 5500 series systems, enabling Solaris to leverage the advanced features of the chip set.
Please note that this does not in any way imply anything negative about SPARC. Solaris is committed to supporting both x86/x64 and SPARC architectures to give you choice.