I listen to a lot of podcasts; one of the minor perks of my job is the freedom to have my ipod playing while I work, and a podcast can really fill in that ear-time.
One podcast I listen to is Writing Excuses, hosted by four (formerly three) published professionals of various disciplines and areas of expertise. It can be very informative and educational, and I feel like some of the things I've heard on it have pointed things out to me that I had noticed but never really understood. That sort of thing is helpful, I can promise you.
But the best lesson I've learned from this podcast - or from any other source of creative advice - is that people are not generally right about most things. Writing, like any other creative exercise, is completely subjective, even in non-fiction. What one person says is right, even necessary, can be disregarded entirely on a whim and the writing can still be good. Cormac McCarthy does not use quotation marks; this is wrong for many reasons, but his books are still both amazingly written and amazingly successful.
Writing Excuses tends to be more centered on speculative fiction (sci-fi, fantasy, etc.) but the majority of the topics and tips apply to much broader subjects, so I recommend it for just about everyone. And if anything they say sounds wrong, remember that you're allowed to ignore it. You should do things your own way.
