NPR has audio and video podcasts of not only this year, but many previous years’ artists on their site: All Songs Considered.
Jack White made a surprise visit and a parking lot performance a few days ago. He also introduces a new artist on his Third Man Records Label, Seasick Steve who blew me away.
There is an RSS feed of the releases of the podcasts.
I found this ethereal performance by experimental folk musician Julianna Barwick intriguing: