This is weird. I can send and receive as long as the recipient is one of my buddies. If they are not a buddy, I never get a text. I use Trillian as a client, and the Google Talk setting to ignore messages from people not in my contact list is turned OFF, so this should be working.
I'm mainly testing this by sending test SMS messages from GVMax. They all show up in my Google Voice app on my phone, but I never see anything in Trillian (on phone, Windows, or Mac clients.)