Here's a shortcut solution to synchronize your phone (or whatever) with your Mac using iSync. It assumes you're already setup for manual sync, such that you would do the following:

1. launch iSync
   
2. click "Sync Devices" button
   
3. wait for sync to finish
   
4. quit iSync
   

To make this a one-step process, open "Script Editor" (Applications > AppleScript > Script Editor), then paste the following:

tell application "iSync"
    synchronize
    repeat while syncing
        delay 1
    end repeat
    quit
end tell

Save the new AppleScript somewhere, and name it something descriptive like "Sync my phone". Also, be sure to choose "File Format" of "application", disable "Startup Screen", and disable "Stay Open".

When you're done, you can do a full sync by clicking your AppleScript application, and then it will clean itself up and let you continue doing whatever you were doing before.