I think enough folks have chimed in, but I too regularly travel with a bottle of wine (or two) -- I like to bring special bottles on certain trips, and it's never been an issue. I have Wine Diapers, and soft side luggage, zero issues.

Just make sure you put soft stuff around it, and pack it in something that could absorb the liquid should there be an issue. Unless there is just a weak point in the bottle, or the bottle somehow works its way to the edge of the bag, and a handler decides to abuse it, I don't see it breaking.