As Tom Hall points out, outside of the Generation DIY series, there are a couple of Mumblecore movies with significant minority presence
In the meantime there is some important info. to communicate; at a long conversation me & Tom Hall are having at the comments in this blog (see recent post re: '06 Swanberg quote) & AJ Schnack's blog, Tom has pointed out that beyond the Mumblecore films at IFC Center's Generation DIY series, there are a couple of other Mumblecore films that do have significant minority presence. He points to Aaron Hillis's (sp?) Mumblecore chart at Cinephiliac (link later) & reminds us that David Gordon Green's film Goerge Washington featured a young African-American actor in the main role, and also that the film In Between Days was directed by an Asian American director and features an Asian lead.
Also, as I've said at several times, of the films at Gen DIY series, Bujalski's Mutual Appreciation does feature a significant minor character (the radio DJ at the begining of the movie) who is played by a minority actress.
OK, off to get more coffee and wake up more, will be back on this topic later; will add more details to this post.
Further, Mike Tully and David Lowery may have been trying to communicate the same info. that Tom did; in recent e-mail & comment section discussions.
My recent post (the "100 million minority" one) that started this conversation was primarily about the lack of minority presence both in front of & behind the camera in Mumblecore movies in the Gen DIY series at the IFC Center - the event that has received the most mainstream and indie film media attention since the start of the Mumblecore movement.