I tend to de-emphasize the word "Christianity." Instead, I employ phrases like "following Christ" and (rather obviously) "spiritual journey." It's often awkward to speak this way, but I find myself doing it—using ambiguous terms like "friend" and "follower" and "disciple" and "journey," and then qualifying them with the word "Jesus" or "Christ." In a very real sense, "Christianity" carries with it a host of connotations that I'd just as soon not deal with. I want people to think about what I'm saying, rather than be side-tracked by negative (and unrelated) associations.
There is always a tension between pedantically insisting on the 'correct' word and being understood. Sometimes this is cultural: there is the story of the American and British students who had gone see their lecturer, and upon being told by her secretary that she would be 'with them presently', the British student went back to the library and the American waited at the office. Or as my webstats page now says "the data will be displayed momentarily", probably meaning "in a moment" rather than "for a moment" (although with BlogPatrol's reliablity you cannot be sure).
I read a comment on the news coverage of Katrina that one startling change was that people were using the word 'poor' rather than 'disadvantaged' or 'economically deprived' or whatever. And on the whole it seems a more honest word, unless (as may be the case), the rich feel that it carries with it the implication that the poor will be always with us (and so nothing need be done about them) or that they are poor because they are made that way ditto).
Other words have dropped out entire. I was shocked to hear on 'Will and Grace' someone say "So that's Dr Motley- I imagined he was an old Jew saying 'You call this dinner?'". Not because it is intrinsically shocking (the speaking character was Jewish, by the way), but because I have grown completely unaccustomed to the use of the word 'Jew' in any sort of comic sense. What is still a bit troubling is that the joke was clearly using the word to imply a stereotype. Children's joke books have problems these days- the great stock-in-trade of Irish (Polish, etc.) jokes reliant on their butts' stupidity has become almost unusable that that they have to be re-cast as "did you hear about the stupid person who did something stupid?". Small loss, perhaps. It is notable that the 19th century Punch cartoons that kicked off the Irish joke tradition was less coarse than is often said. When the Irish peasant tells the lost motorist who asks for directions "I wouldn't start from here", the joke is on the motorist. Much more objectionable are the Punch cartoons whose humour relies on the stupidity of servants in interpreting the words of their wiser, richer, lazier, and better-educated masters. Ha bloody ha.
Word fashions come and go. To UK ears, the American 'person of color' hardly seemed an improvement on Negro, although that may not have been the word it was replacing. I think it will be something of a Red Letter day, though, on the first time I actually call someone a nigger on the grounds that they would want me to.
Sometimes people resist word tanking: Bob Dylan, on 'Time out of mind' goes out of his way to use the word 'gay' in its older, non-sexual, sense: "strumming a gay guitar", "I've been to London and I've been to gay Par-ee". In general, though, we have to face the fact that communication is communication, and it is our readers' verbal associations we must consider, not our own. This is the reason I would never say "I am a poet"; "I write poetry" is not just less of an extravagant claim, it also attempts to sidestep the opinion held by many that anyone making such a statement is bound to be sentimental, alcoholic, dying, or impractical.