AT&T offers mobile backup solution.

"AT&T Mobile Backup functions as a small application downloaded to your handset. Once activated, the service [provided by Asurion Mobile Applications] begins an automatic backup process that can be scheduled at the interval of your choosing. Once the system has uploaded your info, it becomes available via an online interface."

related: Mobile Analyst Watch: AT&T offers mobile backup solution
"I would like to protect other mobile content and apps, system state info, etc in case of disaster (i.e. break or lose phone). I currently back up this data to my phone's microSD memory card, but if you lose the phone, most likely you lose the backup too. So is there an OTA backup service for this? Is there even a market? How about for the enterprise?"