This is an admittedly minor bug/issue.
I am subscribed to 11 podcasts - 9 of the feeds show the individual podcast length perfectly. 2 do not. They download fine, play fine - and the length shows after I start listening, but after it is downloaded and before I start the podcast it shows "???". Is this a podtrapper bug or something on the podcast side? The two feeds I have with this problem are WNYC's Radio Lab (http://www/wnyc.org/shows/radiolab.index.xml) and CNET's Buzz Out Loud (http://feeds.feedburner.com/cnet/buzzoutloud?format=xml).