What happens in Vegas doesn’t always stay in Vegas.
The two largest U.S. mobile operators, AT&T and Verizon Wireless, have used the Consumer Electronics Show in Sin City this week to stress that they aren’t betrothed to any one smart phone platform. Far from it, both operators seem keen to portray themselves as promiscuous.

The underlying message seems to be that, after the extraordinary momentum achieved by the iPhone in the past three years; the big U.S. operators are very alert to the dangers of becoming dependant on one or two vendors in the smartphone market.

Seemingly preparing for the day when its iPhone exclusivity expires, AT&T announced plans to launch devices running Google’s Android platform and Palm’s WebOS software, in addition to the BlackBerry OS, Symbian and Windows Mobile smartphones already in its range. In a coup for Qualcomm, AT&T said it will also use the chip vendor’s Brew system to deliver apps to what it calls “quick messaging devices”, which are essentially feature phones.

Meanwhile, Verizon Wireless, after declaring its affections for Google at the end of 2009, announced plans to rollout Palm WebOS devices. In 2010, that means Verizon will be offering smartphones running Android, BlackBerry OS, Palm WebOS and Windows Mobile, as well as a bunch of feature phones supporting Brew.

Whereas the large mobile operators, such as Vodafone, used to call for fewer smartphone platforms to increase the industry’s economies of scale, it seems that they may now be a force for fragmentation. Verizon and AT&T’s increasingly enthusiastic backing of Palm, in particular, seems designed to ensure that Apple and Google don’t carve up the consumer smartphone market between them. The operators appear to be trying to ensure that the developer community doesn’t rally exclusively around the iPhone OS and Android – a form of divide and rule.

For apps developers targeting the U.S. markets, all this operator promiscuity means they will have to support perhaps five major platforms or gamble on which operating systems will ultimately win out.
Despite what happened in Vegas, for small developers forced to choose, Android and the iPhone OS are still clearly the safest bets. Outside of the U.S., Symbian also has to be on any short list.