As I mentioned before (Acceptance Testing Guidance, Grigori's Take on the Acceptance Testing Project), I am working on guidance around acceptance testing with Grigori.
We now have alive CodePlex site that we can work from: patterns & practices: Acceptance Test Engineering Guidance
We will be posting more as we really get ramped up. We have a LOT of ideas that we will post and talk about. We will also post bi-weekly (or close) drops, probably in the form of Word documents, showing what we have so far, and asking for input.