A quick note regarding the implementation of the iCloud version of Back to My Mac. According to Apple's support article, Mac OS X: Using and troubleshooting Back to My Mac with your iCloud account on OS X Lion, Back to My Mac under iCloud can connect only between Macs running Mac OS X Lion (and 10.7.2 or later). This means, for example, that you can't use it from a Lion-ized Mac to control a Snow Leopard Mac, nor vice versa. Also, according to the support article, What happens to Back to My Mac after I move to iCloud?, you cannot use iCloud's Back to My Mac to access Time Capsule nor AirPort disks remotely.

—Posted by Michael E. Cohen on November 2, 2011