Very nice pick-up!
Since the .com was a heavy-hitter, you should be able to at least get some ppc traffic from these if not get a contact email from the owner of the .com (if it is a company rather than someone using the domain name as a ppc site) with interest in purchasing these domains from you.
If they come after you with a legal battle, you better make sure you edit your first post and make sure that it is not know that you registered this domain in spite of the sale of that domain.
Overall it shouldn't be a big problem, you registered based on the sale of a domain before the real mark was acquired.
The only downfall is that this ebay sale might be fraudulent, in which case you might be out like $20.
Not a risk with the potential outcome being as high as it is.
Best of luck
-Steve