Know what gets under my skin? If someone asks, "What religion are you?" and the askee responds, "Well, I was raised blah-de-blah."
This happens on the radio all the time. Don't get me wrong -- I fully acknowledge that it's tough to answer an obnoxious question with grace, so the askee is at a disadvantage. I mean, someone only asks this question so that they can get into the mindset, theoretically, of the askee. Well, I've got news for ya: there's not a lot of ipso facto in the world of Catholicism. Many a Catholic deviates from Church doctrine on the finer points of birth control, charity, attendance, etc. Some would call this buffet-style religion (you only put what you want on your plate and leave the rest), which it may very well be, but that's a whole 'nother blog post.
So, we've established that I'm annoyed by the question in the first place. Then, though, my annoyance is exponentially increased when the askee deflects the question by providing only the religious affiliation of his youth. Just say, "I don't really practice anything," or, "I'm not comfortable answering that," or "I'm agnostic," or "I'm an atheist." It's okay to be these things, so don't hide behind former religious affiliations. And if you converted, state your current religious affiliation. Why's that so hard?