As I was enthusing to my friend and former business partner Doug Levin about the quantity of open source telephony software I saw at ETel this week, he remarked about the amount of open source that was Frankencode - software of dubious provenance and unknown reliability. Doug should know. His company, Black Duck Software, is kind of an automated policeman to track an organization's software assets. I guess asking him about software is like asking a cop about human nature - he sees all sides of it.
That said, there is a sizable movement behind Asterisk and the company behind it, Digium, attracted $13.8 million from Matrix Partners last summer. And there are a number of open source handset projects, including the Qtopia Greenphone and OpenMoko. However, as Alex Russell pointed out at the conference, the wireless operators view such efforts the way the characters of Shelley's novel viewed Dr. Frankenstein's creation.