Cycling '74 has released Max/MSP v4.6 (and Jitter v1.6) which adds Universal Binary support for Intel-based Macs running OS 10.4 or later.

Max/MSP v4.6 and Jitter v1.6 are free updates. Max/MSP v4.6 and Jitter v1.6 for Windows will also be free and available in September.