Feeling conned by the promised “push” technology of MobileMe, specifically when making changes on your Mac, only to find out that it will not push, but instead, sync at 15-minute (60 minutes in 10.4.11) intervals? I found the .plist file that controls the “Automatic” sync interval for MobileMe, and changed it from 15 minutes to 1 minute. The file is located in ~/Library » Preferences » ByHost » com.apple.DotMacSync.your_MAC_address.plist.
Open this file in Property List Editor, find the AutoSyncInterval key, and then set it to the number of minutes after which you want it to sync with the server. I have it set to 1 right now, and it syncs every minute which is good enough for me at the moment. Hopefully this will be of value to anyone who needs something more immediate than a 15-minute sync, and doesn’t want to bother with Manual sync.