This has been asked of me recently by acquaintances who thought I was a Protestant Fundamentalist Prairie Muffin, but see that I read Catholic and LDS blogs. ;o)
I grew up in a liberal Mennonite church, have attended Raphael (European Four Square) fellowships, American Baptist churches and non-denominational churches. We currently attend an Evangelical Free church. We are not so big on denominations, but on finding Bible believers to fellowship with in our community. I grew up traveling to a nearby town for church... When I moved to the Netherlands I also traveled 30 miles to another town... When we moved to the States we again traveled 30-40 minutes to find a "good" church. But a couple of years ago Steadfast and I were convicted to bloom, really bloom, where we are planted... Right where we are planted. There were two churches to choose from in our small town... And our first Sunday visiting one, we found out they were merging. ;o) So this is our church, because this is where we are... And we love it dearly.
We are moving to Ohio and the town we are looking at has mostly Baptist churches. Steadfast, being European, has a strong aversion to the name "Baptist"... Even though we have attended a Baptist church and loved everyone there, he was greatly relieved when they took Baptist out of the name and called it a Christian Fellowship. Even though at the heart of it's doctrine it was still American Baptist, he felt better.
I link to LDS blogs, because I read them. There is one especially that always interests me. The Concierge seems to share a lot of the same interests as I, even though our religions vary. I read her blog because she is always finding neat stuff to talk about. ;o) There is also the fact, that in spite of our religious difference, LDS'ers, on the whole, value family values, value moral values, and have that great system for storing lots of food... Something worth learning when you have a larger than average family in Earthquake territory.
I link to Catholic blogs because... Well... I don't think our beliefs are all that different. I have found time and time again that I have more in common with the devout Catholic moms I know than with many women in my own church family. There are few women in my church who homeschool, or even feel homeschooling is right. There are few that believe in letting the Lord plan our family size. There are few that believe birth control is immoral. There are few that believe moms should stay home and raise their kids. But in our local Catholic homeschooling community, I am finding many moms who believe as I do. That's not to say that moms who work, use birth control, or want only two kids aren't saved. That's not what I mean. I'm just saying I don't have as much in common with those women. I do meet a lot of Fundamentalist Baptist type women in homeschool groups who tell me Catholics aren't saved. But there are many former Catholics in my current church, and they have no doubt they were saved while still Catholic, and I have no doubts either.
Just as there are saved and unsaved people walking around in Catholic churches, there are saved and unsaved people walking around in Protestant churches. It's all about Christ and our belief in Him. Christ is the deciding factor.
I think, when God looks down from Heaven at His Church, He doesn't see His people set apart in this box here, and that box there... He doesn't see us divided by lines... He looks down and sees a mass of people and here and there are dots of Light, His Light shining in His People. Like Salt sprinkled around. Like stars twinkling here and there in the darkness. Okay, that's just a visual image... Who am I to know what God sees? But I don't believe He looks at us and sees the labels we've given ourselves, like Catholic, Baptist, Prairie Muffin, Attachment Parent..... He looks down and says "There's my child that I created for my Glory & Joy"
That said... I don't think one official world-wide Church is a good idea. ;o)