At this point, I think all the major vendors that support the Mac support the Intel Macs. It wasn't really that big a transition for driver writers because assembly language, Altivec, and other processor-specific stuff are all generally discouraged in device drivers, and endianness issues are about 99% abstracted by the I/O Kit itself.
Oh, yeah... software... the two most highly recommended apps are Logic and Digital Performer. Both are Intel native in their current versions; both are only recently native, so I would not be surprised if there were a few bugs lurking still, but they should be fairly solid by now.