I'm having a brain fart.  Previously the logic was simply that if the OS is snow leopard or earlier then ssse3 was disabled.  I changed it so that *unless* the OS is lion or higher *and* the CPU reports ssse3 support then ssse3 is disabled.

That's right, no?  I'm having a massive bout of existential doubt ;-)

(In theory it shouldn't really cause any issue for Lion or Mountain Lion because these newer machines will typically be running Mavericks anyway)