One of the shows my wife collects on our new Tivo Premiere is I Love Lucy. Setting up the recordings from a Wish List the Tivo grabs episodes from a couple different channels. They are all 1/2 hours shows. Most of them record at 990 megs. However some record at an average of 3000 megs. Why the difference? It was my belief that Comcast was broadcasting in only digital (since we need cable boxes for each TV). Are their broadcasts still in analog (the 990 ones) and others in digital (the 3000+ mb ones)? Is there a way to lower the quality (and file size)?