Miller seems to have disappeared. Last public appearance was in 2009. Websites are still up. I don't think he has posted to the rv forums for years although Ed Dames was referencing Brent as his partner and best friend as of Oct 2012.

So he is still around just went dark for some reason. I know Dames has been very careful about talking about certain things, as he has said it would be very dangerous for his health.