Well considering I do the same thing at home as the gym it doesn't really matter to me except for the fact that I only have a treadmill at my house and lots more options to choose from at the gym. I listen to the radio and watch the tv at the gym and at home I can do the same thing but most of the time just jack up the volume on the TV so I can hear it over the treadmill and watch whatever might be interesting or put in a DVD to watch.
It does piss me off when someone is chatting on their fricken cell phone right next to me. There are even signs all over the place saying not to do this.
I find it more difficult to motivate myself to work out when I'm at home. I keep thinking of other things I could be doing instead and end up putting it off over and over. Once I actually start working out, however, I manage to stay focused on what I am doing and push myself hard. I suppose it's the same with the gym...just getting over there is the hard part, and after that it's easy.