Do we actually need this?
- Everyone can see that an article is a stub
- It will most likely not be extended soon
It's a nuisance to see a note like this on an article no one has touched for months. Isn't in an embarrasment for those who put the note but then epically fail to deliver. If you have nothing to say, then don't make an article, or put it into your Sandbox. At least, just don't announce that this article will be the unmissable article of articles very very soon.
In constrast to Wikipedia, no one deletes stubs here anyway.
And most importantly, no one will be shocked or complain when an article is expanded without a warning.