While working through some problems with my PDW-U1 and XDCAM transfer I was able to get in touch with a Sony rep, and in our discussions he said that there would be driver updates for Snow Leopard released sometime around NAB.
Sony XDCAM 350 HD, XDCAM Transfer 2.10.0
MacOS 10.6.2, Apple FCP 7.0.1
2x2.66 Dual-Core Xeon, 5GB Ram, 1.5T Internal RAID
ATI Radeon X1900 XT