No, they do not have a SIP interface we can use.  They originate/terminate on the PSTN.  (unless you have a gizmo5 account which are no longer offered).  One would hope they offer a SIP interface again someday...

On Tue, Aug 31, 2010 at 12:32 PM, Malay Thakershi <mthakershi@gmail.com> wrote:
Does Google Voice (paid service) provide SIP terminate/originate like
others (say Vitelity)? If so, what is their cost?

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-Rupa