at least two fatal cargo plane crashes since 2006, including a UPS jet in Dubai." You can check out the video below to see how destructive a lithium ion battery can be. In the meantime, if you absolutely, positively need to ship a smartphone out of North America, third party shippers such as FedEx, UPS and DHL will be more than happy to have your business. Last year, President Obama's administration wanted to change the classification of lithium ion to a hazardous material. The House, sensing a possibility for some economic displacement if such a law was passed, managed to get through a bill that would prevent limitations of the shipping of lithium ion by air.
The USPS will review the ban as the months go by, and could decide to allow smartphones and the other lithium battery powered products to ship through its pipelines again on January 1st 2013. If that decision is made, the one requirement will be that the batteries are properly installed in the phone or whatever device is being shipped.
source: USPS, FastCompany via WPCentral