x86 code is not suitable as a web standard. (And neither is the LLVM intermediate representation, for reasons expounded on in e.g. http://permalink.gmane.org/gmane.comp.compilers.llvm.devel/4...)
I see Native Client as being an extremely nice solution to several issues at once:
- runs fast
- the programs don't need an installer
- I can trust a Native Client program (that's me personally)