Although I no longer synchronize to a Palm device, I can appreciate how inconvenient a 90 day wait is. You can find an official
statement here from Mark/Space concerning Mac OS 10.5 compatibility.
In their defense, I can say that the release version of Leopard has—to some degree—apparently caught a number of developers large and small by surprise, and there are substantial changes and bug fixes in the most recent release of the Sync Service framework that must be dealt with. This is a very complex software environment. That said, there are also clearly significant issues going forward related to synchronization.
I noticed that in the thread you pointed to, that one self-described higher education information technology director was upset enough with Mark/Space to license synchronization software from a competitor. All I've got to offer him is the thought that if he is unhappy now, just wait until he has to rely on software from PocketMac! He has no idea what he is in for…
I won't upgrade to Mac OS X 10.5 for reasons unrelated to such compatibility issues for some time, as Leopard offers a lot of flash but very little substance—in my estimation—for serious business users who must continue to work unimpeded and uninterrupted. It's a lot like the iPhone: a marvelous technology demonstration, but not sufficiently practical or productive for most serious business users. Nor, I admit, did Apple intend it to be. I am frankly less than impressed with this OS release, considering it the most problematic release in a very long time.
In fact, I recently downgraded from Mac OS X 10.4.10 to 10.4.9 to mitigate substantial wireless networking issues. Drops are gone, poor performance is no longer an issue, and 802.1X secure interconnection once again works. It may be months until I am satisfied that Leopard adequately addresses such issues, and it is clear that—in the networking and synchronization areas—there are some very substantial unresolved problems. Whole technology hooks, like the telephony bundle which provides for Bluetooth dialing and SMS, have disappeared. Apple has a big job ahead to address some of these issues that may be meaningless to typical non-business or academic, single-platform users, but critical to others who use these tools.
End of rant and of feeble defense of other developers.