That's the first I've heard anyone say i5 was slower.  Everyone else has said 4way was faster on i5.  Moreso with hyperthreading enabled.

Good, so I take it that's a confirmation that it's working on Mac as well?

Laszlo told me he did compile in the -4way stuff on Mac, so the -4way switch is also available to try on Mac.  I don't think makefile.osx on SVN has it yet, just the built version.