I'm very attracted to the principles of AP, and I don't think that having two at a time will be a barrier to pursuing AP as planned. Are there any AP MoMs here? I was planning on putting both babies in a Arm's Reach at first and going from there exploring our comfort level with co-sleeping/co-bedding. I'm also planning on getting two Ikea mattresses for use in the nursery or to side car one or both of them. Does this plan sound realistic?
TTC #1 2+ Years with Unexplained IF
1st & Only BFP: 1st IVF w/ ICSI, 3dt of 2 7-cell, grade 2 embryos on 8/25/12
Beta #1 9/5: 87.2 BFP! - Beta #2 9/7: 248 - 1st US @ 6w3d Two Heartbeats! - MoDi Girls!

Re: AP Twins
Hi! You might want to ask on the Multiples board. I'm sure that there are some AP mommies over there.
I only have one LO and we bed share, but I recommend looking at the arms reach in advance. Make sure it's big enough for two babies. I love the idea of having them sleep together next to you. They will have spent every moment snuggled together, so that seems very natural to me!
Sidecarring a crib with one side removed could be an alternative if you think that the arms reach will be too small. I have a friend who did this with her DS.
Good luck, and congratulations!