I also just got a TiVo Premier - my first TiVo. I bought Toast so I could transfer video off the Tivo and to watch video files from my Mac on the TV. I'm still waiting for Comcast to come with the cable card, so I havne't tried that yet. I can see the TiVo from my Mac using TiVo Transfer.
But when I am on the TiVo I can't seem to connect to my Mac. I have Mac2TiVo running and I've added a folder of video files. On the TiVo, I go to the "Add Application" entry and type in the IP address of my Mac and I get "no service no ping". Both are on the same network with 10.0.1.* IP addresses. Any ideas?