An excellent article by InformationWeek's W. David Gardner looks at the imminent battle between wireless carriers over the fast-growing Wi-Fi phone market.

"While Apple and AT&T's Cingular Wireless prepare to announce pricing plans for the Wi-Fi-equipped iPhone, T-Mobile is going to up the competitive stakes with a national launch of its Wi-Fi HotSpot@Home service," Gardner writes. "Personnel at AT&T stores said Thursday they're still waiting for pricing plans for the much-anticipated iPhone, which is scheduled to ship next month. T-Mobile's HotSpot@Home service has been tested in the Seattle area for several months at $20 a month."

"In the future, VoIP on Wi-Fi could tear at the whole underpinnings of the [wireless] industry," says Spectral Advantage analyst Joe Nordgaard. "This issue is only going to grow. Operators are going to have to develop strategies to deal with it."

"Other mobile phone providers have been inching into the Wi-Fi and VoIP market," Gardner writes. "Mobile VoIP provider WiFiMobile announced Thursday that its Version 751 software for making VoIP calls over Wi-Fi is available for Nokia N95 handsets. The software, WiFiMobile said, also operates over 3G networks."