I see a list here with a section titled M-theory - http://www.superstringtheory.com/links/reviews.html
In there these two look promising, http://arxiv.org/abs/hep-th/9607201 and http://arxiv.org/abs/hep-th/9802051
I would like to know if people have opinions of good starting points towards understanding M-branes and how they are used for constructing exact examples of AdS/CFT. [...I guess all exact AdS/CFT scenarios are M-theory constructions..]