Apparently, saying "could have been implemented on DX9" in my previous post in regards to VC self-shadowing stired all sorts of drama on some of the user forums. Although the statement is accurate, I did not explain in more details WHY this was not done and why we kept this feature for DX10 only. This post is not intended to be harsh but a mere clarification of why the decision was made. My tone may seem somewhat pessimistic but this is mainly due to frustration from the fact that some of our fans seem to be on a constant quest to crucify us no matter what we do.
Back to the topic of why self-shadowing is only present on DX10, I was really quick and vague into giving actual reasons and wanted to be true and honnest in my statement, which apparently got taken out of context and distorted... Since the VC self-shadowing is essentially another form of shadow mapping as done with the exterior, it could have been implemented on DX9. However, there are two reasons why the self-shadowing of VC was kept as a DX10 features (beyond the force people to upgrade conspiracy theory).