I'm interested, but also stupid this morning:
1. You'll stop adding orders on that domain once you've filled up your ~80 OBLs?
2.  Do I have to use the same URL/Anchor for ALL 47 sites?  I have a few I'd like to split it between, is that possible?
3.  Are the links in different geographical locations, or just different Class C's?
4.  Can I keep the service but change the URLs/Anchors on all?  The site I'm struggling with and considering this MAY not be worth $50/month ROI, but others are.  I am still yet to find out.
5. How are YOU continuing to backlink your domains (if you don't mind)?
6. Will you use Title tags too?  I like these...
Evolution - I'm e-mailing ya.