If you know dogs well, you can tell that this little guy has the commercials memorized -- he knows when the dogs will appear and where!
Reminds me of my little Yorkie who used to love to watch tv and wait for animals. We would leave the tv on for him all day while we were at work. He, too, had all the commercials with animals in them memorized. All he needed to hear was the music for the commercial and he would run into the tv room and wait for the dog/cat/horse/Pillbury Dough Boy/whatever to appear and then bark like crazy. He especially liked the catfood commercial with the beautiful white cat with the "clink - clink - clink" on the crystal bowl.
Watch:
http://www.dogwork.com/tvdoggy2/