[Phanx]

Which isn't really a valid concern, since WoW addons are not a money-making venture and it really doesn't matter one bit if someone else turns your idea into an addon first... also the chances of someone actually taking your idea and turning it into an addon without you are pretty much zero. Besides, if someone else writes it, and all you do is provide the original idea, what do you expect to get out of it other than the use of the addon anyway?

And on top of all that, almost every time a thread like this is posted, once the poster finally posts their actual idea, it turns out to be something that's not even possible in the first place.

I really doubt you're willing to pay someone the actual market value of their time to write an addon for you, so they only way you're going to have any hope of getting an addon written are either (a) write it yourself or (b) share your idea publicly to maximize the number of addon authors who see it and hope one of them is interested enough to write it for free. "PM me to hear my super secret mystery idea!" is just a waste of everyone's time.