Google Worsening Google Voice on May 15, 2014. Dropping XMPP support. No more free "landline" service.

[SMS]

Google is dropping support for Extensible Messaging and Presence
Protocol (XMPP) in Google Voice on May 15, 2014.

If you are using Google Voice with an ATA (analog telephone adapter),
such as one of the Obihai or Grandstream VOIP devices (or a hacked
MagicJack Plus), this combination will no longer work after May 15,
2014. Google Voice is very popular with these devices since together
they enable local phone service completely free of any monthly charges
(but no E911).

The reason for this change is probably because users of these devices
are not seeing any advertising when using Google Voice.

There are no no-cost alternatives, though Localphone and Callcentric are
pretty low cost alternatives, especially if you're not making thousands
of minutes of local calls per month. Ooma is a good alternative as well,
but it costs a bit more and you must use their VOIP adapter.

<http://blog.obihai.com/2013/10/important-message-about-google-voice.html>