I personally see no problem with it at all as long as it is a hey, we developed this cool new application please check it out and full disclosure that you are behind it. I also don't see it being an issue to recommend it if someone has posted a directly related question and it serves that need. If there is a prob I am sure a moderate will say something and if there is a bigger problem sow you made a good faith effort by directing them to this link. Just my views as a forum member.
WildCowboy, do you think there is a difference between direct advertising and general promotion, I was talking about the latter, but am curious. By the way hopefully your little airport issue didn't diminish my fair city.