After updating to OSX Lion I realized that syncing my iMac to my iPad/iPhone no longer gave me the option to be notified about pending changes to my iMac's iCal and Address Book. Given the potential to wipe out all of my data with a single click a fix was needed.
Apple Support was not able to find a solution. Having an older Snow Leopard Time Machine Backup of my machine I searched for iSync in the Applications Folder, copied and pasted it to an external HD, and then copied and pasted into the Applications Folder on the Mac running Lion.
Opening the iSync folder allowed me to set the parameters that I wanted and upon the next sync the hoped for warning message popped up as expected.
[crarko adds: I haven't tested this one. I thought there was a previous hint about this but searching yielded none, so here it is.]
Mac OS X Hints
http://hints.macworld.com/article.php?story=20111123212032607