While state regulation looms large over the growth of the VoIP industry, new providers emerge to give Vonage a run for its money. Michael Robertson, the founder of MP3.com and Lindows, recently joined the VoIP party by launching SIPphone, a Session Initiation Protocol provider based service akin to Jeff Pulver's Free World Dial-up.

Users pay $129.99 for two Grandstream BudgeTone 100 phones (see photo), and pay no additional fees; though unlike Vonage they can only call other SIP service users. Impressions of the service continue to emerge from participants in our VoIP forum. (See these two threads)

Companies like Packet8 are also emerging to offer cheaper alternatives to Vonage. Packet8 offers unlimited calling to the U.S. and Canada for $19.95 a month, and the company is seeing the kind of good press Vonage experienced early on. Despite being half the price of Vonage's offering, not everyone is impressed with the service quality, as this thread in our forums indicates.

Despite a growing field of competitors, the VoIP field faces a growing threat of state-to-state regulation, as we mentioned recently and as Jeff Pulver has been predicting for some time. ISP Planet today offered up their own report on the emerging state-level battles facing the young technology.