I just activated In Post Ads to try it. I came across a couple of issues and don't see any way to fix as yet. I created a test ad, and added some text in it...then activated the ads via the settings, also making it live. I viewed a post and the ad box appeared, with text in it, and a find out more link - which I subsequently realised links to the obscurley named "plugin url", in "link to plugin" box on the ad post creation admin.
This seems to have potential, but has a way to go to make it ready for generic use, unless I'm missing something. The ad box comes out blue background with my text in it, but has the title "Featured plugin: ad post title", the text I added and the readmore link. Obviously set-up for your use in wpmudev.org I assume. See attached screenshot.
I was hoping to have a box I could load some ad zone code or a banner in to and have the box linked appropriatley, or indeed to do a text ad with read more link as you have done, but to have options, not just so hard coded, and ok, I can dive in and style, modify it etc, but it does seem to be half out of the box, as is...
I hope that is some constructive feedback, and I'll wait a bit to use this plugin...
A further suggestion would be to have a post category or tag seclection, so that specific ads could be assigned to specific post types etc...not just show all the ads in whatever sequence by title, date etc, either random or asc/desc - i.e. to have some sort of ad selection, to allow some level of targeting, but simple.