I was following this story in the blogosphere all day, but it looks like it finally hit a big-time news outlet, ABC:

The authenticity of newly unearthed memos stating that George W. Bush failed to meet standards of the Texas Air National Guard during the Vietnam War was questioned Thursday by the son of the late officer who reportedly wrote the memos.
"I am upset because I think it is a mixture of truth and fiction here," said Gary Killian, son of Lt. Col. Jerry Killian, who died in 1984.

Another officer who served with Killian and a document expert also said Thursday the documents appear to be forgeries.

Instapundit has a good roundup. Here's Wizbang's blowup of the side-by-side...the top image is the "original" and the bottom is a fake produced with Microsoft Word in about 5 minutes. Run a few generations through a copier, and there you go.

The shit hit the fan in the blogosphere this morning, but Nightline has apparently picked up the story, and the shit's probably going to hit the fan in the mainstream press in the next couple of days.