Although I think it's terrific that Google is opening up their API's, we shouldn't forget the
recent security problems with SOAP::Lite.
I'm not saying this should stop you from going ahead and tinkering with this stuff (I'm sure going to ;-) ... just be careful out there. It seems that it is fairly easy to abuse servers running the SOAP::Lite module, to the point where I heard somebody claim they wrote a script that gave them root access in under two hours. (They also claimed to be somewhat inexpert with Perl, amusingly enough.)
I'd wait before deploying this on a production box.
Anyway, I've gotta get back to this PHP project, see ya around!