Sean Alexander brings up a good point that has been nagging me for a while - the lack of idents at the beginning of podcasts. And by begininning I mean the very beginning. Before any intro music.
I listen to a lot of podcasts in the car and I have no visual clue as to what is playing. If you don't ident your show at the very beginning, then after 10 seconds I've skipped your show because I have no idea what it is and I've got plenty more shows to fill the short time I have to listen to them.
On another note, Adam Curry used to ident the Daily Source Code with a date and then changed to identifying it purely with a show number. I have no idea why. There is no way I can remember the number of the last show I listened to, but I might be able to remember the date.
So, please ident, and please include the date.