(This article was first published on Search Results for R, and kindly contributed to R-bloggers)
Aleks pointed me to this site by Alexander Genkin, David D. Lewis, and David Madigan that has a program for Bayesian logistic regression. It appears to allow some hierarchical modeling and can fit very large datasets. I haven't tried it...
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Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).