Dug a little deeper on the above post by Saygracenow and found this:

http://thekey.xpn.org/2012/05/09/wxpn-broadcasting-non-commvention-shows-with-grace-potter-war-on-drugs-willie-nelson-rufus-wainwright-brandi-carlile-polica-norah-jones-and-more/

WXPN will be broadcasting and webcasting the following sets live:

Wednesday, May 16
 8:00 PM – The Key Studio Sessions Live with Graham Alexander, Find Vienna
 10:00 – Grace Potter &amp; the Nocturnals