My Nexus One got the Gingerbread update the other week. One of the new features is built in SIP support (which you can find at the bottom of Settings -> Call Settings). It was reasonably straightforward to get it talking to the IP-01 (note to self: remember to click on the "Apply Changes" button in the top right corner after making changes). Sound quality needs a bit of work (I have a feeling some reconfiguration is in order).
I think I'm going to have to look into Locale scripting for turning "Receive incoming calls" on and off (if I'm not at home then there's not much point wasting battery while trying to keep in contact with a server it can't ever see).
One thing worth noting - if you normally don't bother with passwords on your SIP accounts, you'll need to have one on the account you want to use with Android as you currently can't set up a SIP account on the phone without one.
Google Taketh Away
I got an email at the weekend - Gizmo is getting shutdown. Apparently Google think Google Voice in GMail is a more than adequate replacement. I disagree on two counts.
One - the lack of SIP support. My hope is that SIP support for GVoice is coming soon (though you would think they would have gotten that up and running before shutting down Gizmo). After all, it's now built in to Android. It's probably best not to hold your breath though.
Two - US-centricity. Both Gizmo and Grandcentral were international. Google Voice is not. I had to go through hoops to keep my GrandCentral number working with Google Voice while in the UK that I did not have to go through with GrandCentral. Gizmo helped on the international front as it meant I did not need a second US telephone number to use GC and even after the move to GVoice it made things a lot easier. Now I'm going to have to go through even more hoops to keep using the service. I really don't get why Google so often fails when it comes to looking beyond America's borders (it's not just Google Voice where they often fail, but Voice is the poster child for Google's failures in this regard).