Two things. Like the name Jamcasts and came up with it seperately for many of the same reasons as you but mine is for a business purpose. Jamcasts to me stand for Just A Minute podcasts.

I have formed a new business to provide busy executives with daily one-minute audio summaries of news and information from a wide variety of industries.

Secondly I have been using Typepad since it began. But thinking about using MT or Drupal as both support larger communities and also have RSS2.0 and tag support. Question: Do you find MT easy to use?

Thanks and good luck

Sam