Garret Smith writes some thoughtful words about WiFi phones in his blog:

Infonetics Research released a report that showed WiFi ip phone sales increase 60% in 2007, with 682,000 units were sold worldwide. The report cited “increased vendor support” as the primary reason for the growth. 

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While some people seem to like WiFi phones, they aren’t for the faint at heart, especially if your aren’t technically savvy. My advice, if you want to go wireless, is to pickup a DECT based solution. A little more expensive, but it works…for everyone. 

I still haven’t met a WiFi SIP phone I liked and used more than a couple of days…