Really, what is this feature waiting for?
It's not exactly a trivial feature. At the very minimum, I would need:
- Some mechanism for sponsors to pay for and submit ad images.
- An ad server to select and keep track of ads for display.
- A method for ad image transfer to the client.
- A method for ad display on the client.
Given my limited development time, that could take months. Plus, when I start making a profit off of this, there may be legal issues that need to be sorted out.