Well, I know I am the extreem minority here

but we are an AP family, do not believe in CIO, do not spank, have a family bed, breastfeed on demand (even at 16 months old), wear my children ...
Our first son was our "guinea pig" so to speak. We did try the cio thing but it didn't last long ... unfortunately I let him wean too early and also did not push the co-sleeping with him. When our second son came, we had learned a lot (imo) and changed a lot of our beliefs. Even though our older son has his own bed, usually one of us falls asleep with him or at least lays down with him while he is falling asleep. Our younger son has slept in our bed since the day he came home. He is nursed on demand; yea, there are times I wish my body was off-limits to him

but it's my selfishness I believe. I do not believe babies are capable of manipulating their parents. God designed them they way He did so that they would know how to communicate their needs - their needs to be feed, changed, and most importantly LOVED. I have seen enough first hand the affects of cio, and have read studies. I have also as a child and adult cried myself to sleep and would never want that to be experienced by my children.
Sometimes I sit back and think, What would Mary do. You know, she had the amazing and awesome responsibility of raising the Son of God. And you know, I don't believe that she would have let Him cry it out in His own room. I just don't see that happening. God does not let us cry it out by ourselves. He is always right there next to us, even in the darkest of times. That is how I believe we are to be with our children.
Isaiah 66:12 - 13 (NASB) 12 For thus says the LORD, Behold, I extend peace to her like a river, And the glory of the nations like an overflowing stream; And you will be nursed, you will be carried on the hip and fondled on the knees. 13 As one whom his mother comforts, so I will comfort you;
I also want to address the idea that AP means neglecting your husband, or pouring all your energy into your children. To me, AP'ing is being attached to your children - not only physically (as evidenced by breastfeeding, co-sleeping and baby wearing) but also emotionally, mentally, and spiritually. It is to me, making their overall wellbeing a priority over, at times, your own needs. It is realizing the impact your words and actions have upon their development. It is understanding that they are babies - even at 3 1/2 years old - who need support, comfort, reassurance, and unfailing love. It is about builing trust with them - that they will instinctively know that you are there for them, even when they are upset for seemingly no reason at 3:30am. It is about building an interdependence with them where they know they are a valued part of a family that works together for the good of each other above their own gain.
Yes, there are times where my husband and I realize we haven't had time to connect. But it's not just because one of us went to sleep with one of the boys. It's life in general. So, we talk and make ways to spend more time together - whether that be by getting the boys down together (putting them both in our bed to sleep with each other) and then spending quiet, intimate time together in the living room, or scheduling a date and having our babysitter come over for the evening.
I also encourage my boys to play independently and with each other. There are times I will put down what I am doing and sit and play with them. They will only be this age for such a short time. But, there are times I tell them that they need to play for a while so that Mommy can get some work done. There is nothing wrong with putting on the TV (I'm actually trying to figure out how to turn it off more!) or getting them started playing on their own and letting them develop their imaginations. Personally, I do not consider my children my friends - maybe when they are older, married, and parents themsevles. But they know and we know that we are Mom and Dad and they are the children. Being AP (and by extension grace-based in parenting) does not mean giving up the "authority" of being the parent. It does not mean letting the child do whatever they want. It does mean fostering a relationship with them where they trust you have their best interests in mind, where they trust that you will be there whenever they need you, and where you are cued in to their needs/wants/desires. It's about reading their cues and responding.
If you are looking for a good description of AP'ing, I would highly suggest Dr. Sears. He is a Christian doctor and has some wonderful advice and insight into how to raise attached children and yet still maintain a sense of who you are and who you are married to.