The new Big Star album (currently untitled) is set to be released August 28th on Rykodisc. You can pre-order it at Not Lame here (soundbites will be up soon): http://www.notlame.com/Big_Star/Page_1/CDBIGSTAR1.html
Also, in this month’s issue of Mojo magazine (Oasis on the cover), there is an article about the album and some quotes from Jon.