First, the usual caveats about any government report issued by an agency who oversees any program that can be a political football.
Second, Michael Astrue is a Bush appointee, and therefore a Republican. This automatically makes any report he issues in a Democratic administration suspect but particularly so in an election year, and especially given his heavy personal financial support to Mitt Romney.
Third, the answer, not mentioned in the WSJ article, is actually pretty simple: raise the ceiling on Social Security taxes and expand both Social Security and Medicare to income generated from all sources above a certain level.
Permanent solvency. End of discussion. Any questions?