Aside from showing the degree to which reporters have internalized the GOP's admonishments, the rebuke was remarkable for two reasons. First, Pelosi never said that Bush advocated privatizing the entire Social Security program, only that he supported "privatization." Second, as a matter of fact, Bush has advocated privatizing the entire program. In 2000, he said, "It's going to take a while to transition to a system where personal savings accounts are the predominant part of the investment vehicle.... This is a step toward a completely different world, and an important step."
The problem here isn't that the phrase "personal accounts" is any less accurate than "private accounts." It's that the media have abandoned a long-standing and perfectly accurate phrase for entirely partisan reasons.
There's no reason why this would stop with Social Security. From now on, why shouldn't both parties lobby the media to replace any inconvenient words with poll-tested equivalents? For years, Democrats have used euphemisms of their own, like "revenue enhancer" instead of "tax hike," or "investment" instead of "spending program." Yet it's never occurred to them to browbeat the media into adopting their lingo. But why not? After all, those terms are accurate. Tax hikes do enhance revenues, and many spending programs are investments. Democrats have every incentive to denounce terms like "taxes" and "spending" as biased, and to demand that the media give their preferred terms equal billing.
You could see political discourse diverging into two separate paths, one conducted in Democratic English and the other in Republican English. Alternatively, the media could decide that they're not going to change their language just because one party took a poll.