Firms are still faffing about the Universal Power Adapter:

In China, where 500 million cell phones were manufactured last year, the government has regulated that all cell phone chargers, including those imported, have a standard USB interface and output voltage, so consumers don’t need a new one with every new phone.

Such regulations are unlikely in the U.S., but if the industry doesn’t get its act together then the federal government may start to intervene in some way