Edited a few posts

Unblocking with google voice no longer seems to work - let me know if you discover otherwise.
http://nyphonejacks.blogspot.com/2011/05/unblock-private-callers-with-google.html

Added additional information towards the bottom of the page concerning LNP (local number portability)
http://nyphonejacks.blogspot.com/2010/08/lnp-local-number-portability.html

Linked the Gizmo + Google voice post
http://nyphonejacks.blogspot.com/2010/07/free-phone-service-with-gizmo-google.html
to the newer article about the ATA that you can use Google Voice with
http://nyphonejacks.blogspot.com/2011/05/use-your-google-voice-number-with-ata.html

Added important information about call forwarding, especially important for businesses porting their numbers.
http://nyphonejacks.blogspot.com/2009/12/how-to-set-up-call-forwarding.html