I hope this doesn't sound hopelessly secular, but I feel one of the benefits of having a denomination is being able to go to a church anywhere in the country and be surrounded by familar liturgies and songs and such just like folks might be comforted by finding a McDonalds in a strange town and knowing exactly what they want to order. There's a degree familairity and consistancy there that one comes to expect from a "name brand" church. I wouldn't want to walk into church one day or visit a church in another city and find out they've done away with weekly communion so they can sing extra Amy Grant songs (No offense to Amy Grant, who I actually think is an excellent musician). It seems like if I visit a Lutheran church in another town I'm liable to find variations exactly like that. In the Episcopal Church, obviously, there's a certain tradition of divergent thought, but also a tradition of uniform liturgy thanks to the Book of Common Prayer. I've really found it to be a perfect fit for me -- freedom of belief, uniformity of the basic liturgy. There's a spirtual comfort and sense of communion with generations past that comes from doing the same thing over and over again in a way that is universal from city to city, it's part of where the "catholic" part of the Nicene Creed comes in.
It's not a moral issue, but for me in discerning what denomination to join, the congregationalism of Lutheranism was a big mark against it. Martin Luther is probably my favorite theologian and in theory a church that follows Luther should be perfect for me, but I just never felt comfortable with the lack of universality. I checked out two different Lutheran churches and neither used the creed at the services I attended and one basically had no coherent liturgy at all and just tossed songs up on a projection screen and had a 25 minute long set of announcements that compromised nearly half of the liturgy. I also really wanted weekly communion, which was something that Martin Luther himself was in favor of! As it happened, my local Lutheran congregation did have weekly communion, but just knowing I could move somewhere where they wouldn't or drop by a congregation if I were out of town and miss communing was a very difficult idea. The anarchy of the whole setup was very disconcerting for me given my Roman Catholic background.
You can imagine what happened when I visited a Methodist church for a couple weeks! The time they put the gospel before the Old Testament reading just about drove me to drink, which is of course doubly a sinful thought if you're a Methodist (Who traditionally don't drink, though that is changing). ;-)
I'm probably mildly OCD, but I seem to fit right in with Episcopalians. We had a fun conversation a few weeks ago after a traditional service about how much it annoyed us that people kept wandering in and out of the contemporary service slamming doors during the sermon and how distracting it was (When someone brought it up it was like she read my mind, because that had been a pet peeve of mine for a while).

I really love the beauty of the liturgies we have and the reverent and respectful way that they are conducted with such attention to detail -- even the contemporary service. ;-)
John