The announcement on the front page of the forum reads:
"We are working hard on integrating Microsoft Solver Foundation into a larger analytics framework that will help users build both prescriptive and predictive analytics. We look forward to releasing this new product for your use as soon as we are able
to do so. This new product will provide a migration path for current Solver Foundation users and partners. "
That was 7 months ago, and there has been no other information since. I have my doubts if there will be a replacement.
Nate