Deadspin has a decent synopsis of it up now
. The Inner Ring posted a very good
article on it earlier today.
Obviously no one knows exactly what the evidence USADA claims they have is. A lot of what is thought to be the evidence is outlined in both those articles (they weren't technically failed tests, but they are samples consistent with doping). All of it will come out eventually as most of (if not all, I'm not sure, haven't been following EVERYONE involved in the conspiracy accusation) the rest implicated have already agreed to arbitration.
Obviously none of this is enough to make a judgement at this point. The rejection of arbitration, especially after a Texas judge ruled against him on it, throws fuel on the circumstantial/heresy fire. IMO, his biggest mistake in general was the association with Michele Ferrari...
Anyway, things will get much clearer once the other arbitration hearings start. Especially if those "10 plus" witnesses turn out to be who they're rumored to be.