What has been learned from this experience is this:

1) Google does not have an algorithm to detect what they consider excessive reciprocal linking. Instead they rely on others to point out their inadequacies.

2) Virtually every major market area is still dominated in SERP's by real estate agent sites that have as many, if not more, reciprocal links than those sites that were penalized.

3) Some spam reports and reinclusion requests obviously carry more weight than others.

4) Google enforces rules as they see fit. For example, almost 2 months ago Matt Cutts gave an example of excessive reciprocal linking on his blog:

http://www.mattcutts.com/blog/google-hell/

Today that site still maintains a #1 ranking for "engagement rings," yet still has a massive directory of reciprocal links:

mysolitaire.com/resources/

5) You can't fight this battle for reinclusion the way it has been fought.