"Please send a patch"
On the gripping hand, Matthew, notice that patches written by someone utterly unfamiliar with the code in question aren't always welcome. While some people don't mind spending several days on something that may or may not be accepted to begin with, it's important to realize that talking about wishlist items before even thinking about possibly writing a patch is more likely to result in the desired behaviour than writing and submitting patches in a fire-and-forget manner. In that light, there are cases where 'please send a patch' can be quite demotivating, and it makes sense as a developer to engage in a discussion about a wishlist item, even if you're not immediately interested in implementing said feature yourself. Such a discussion could lead to either you implementing it, or someone else implementing it, or the other person finally understanding that your vision for the software in question doesn't match theirs, and that they should just find something else to spend their time on.
I guess the moral of the story is: as a user with a wishlist item, you should talk to developers, let them know what you think is important, and be prepared to write a patch yourself if needs be and you have the skill. As a developer, you shouldn't interpret every wishlist request as a question to 'please please please implement my pet feature', but as an opportunity to reconsider your views, and possibly implement some nice new feature that you hadn't thought about originally but which you think might be nice, too.
If people reply with 'please provide a patch' to each and every wishlist request, they're stupid; even more so than users who think they have anything to demand.