Its high time that they also released an api for google voice[1] . If there are any googlers reading this: why has this not been done yet? I've been looking into this in my spare time as there is no google voice client for Meego (Nokia N9) and I wanted to write one/improve an existing one[2]
My perception for all of this is that Google Voice is a deeply controversial project to people like cellphone networks, who Google need for Android. That's why we haven't seen APIs, VOIP calling, etc. It seems to be stuck in a rut, and I suspect it's political rather than technical.
[1] http://stackoverflow.com/questions/1668619/is-there-a-google...
[2] http://code.google.com/p/qgvdial/