I can confirm that 10.6.3 was indeed the last version to completely and properly support WiFi Sync as described by Apple. The strange behaviors and errors started afterward. I can even confirm that if you revert to 10.6.3, devices will sync wirelessly again without any workarounds, charms, prayers, etc. The only issue there is that I have no idea if 10.6.3 will properly support newer devices, as I now have an iPhone 5 and iPad 4th generation. I have not tried syncing these two devices with 10.6.3, but I can confirm older iterations of these devices will work properly. This is on Windows 7 x64 AND Windows 8 Pro x64.