Gmail + Growl: Make Gmail Notifier roar

I didn't create that headline, the makers of the software did. Gmail+Growl is essentially a Growl plugin that works with Gmail Notifier to create Gmail alerts via Growl. Make sense? For those of you unhip to the Growl scene, it's been mentioned on TUAW a few times before, and is quite popular around here. I had to turn it off because my iBook can't even handle the bezels for volume, never mind the inevitable Mail barrage Growl invokes. But that's a story for another day. You Growl and Gmail fans rejoice.