Part of the problems seems to be Republican media doesn't focus enough on domestic issues like Social Security. I go to blogs like TalkingPoints and Koz and they're always talking about Social Security. Then I go to Instapundit and PowerLine, and rarely do they mention it. Sites like Newsmax and Townhall also don't cover it in great detail. We talk a lot about foreign policy- Iran and N. Korea, but we seem to be non-chalant about issues within our own borders.
I think you're right. Compared against all the talk about Social Security, the real looming crisis in Medicare/Medicaid is a hushed whisper.