Okay, so I posted yesterday that I've decided that a PDA without top-notch desktop sync support is worthless, and that Palms are the only PDAs that sync right with OS X. Great timing--according to Brighthand, PalmSource isn't going to produce an OS X sync program for "Cobalt," their new name for PalmOS 6.
It's not really the end of the world--it's unclear if the basic sync protocol has changed, although the formats used by the native PIM applications is different. So, there's a chance that Palm Desktop 4 will work along with a small update to iSync (which replaces the native PIM conduits in Palm Desktop). Failing that, Mark/Space has committed to producing an OS X sync solution, and they've been pretty good in the past.