Wow, this is big.
Andy Pettitte (picture, right, by Nicole Gottwald) admitted using human growth hormone to improve his recovery time while he was on the disabled list and has issued a press release.

If what I did was an error in judgment on my part, I apologize,” Pettitte said Saturday in a statement released by his agent. “I accept responsibility for those two days. …
“Though it was not against baseball rules, I was not comfortable with what I was doing, so I stopped.
“This is it — two days out of my life; two days out of my entire career, when I was injured and on the disabled list,” he said. “I wasn’t looking for an edge. I was looking to heal.”

The fact that Andy Pettitte came clean means a lot.
It shows the class of Andy Pettitte. He was “caught” using HGH (implicated in the Mitchell Report) and he’s come clean about it. History smiles on those that come clean. Jason Giambi isn’t the subject of much vitrol on the subject, and as Curt Schilling says:

This is a pretty damn forgiving country. We are all about giving people second chances. The quicker anyone guilty is accountable, the quicker we can all move on and hopefully make this thing go away, and fix what needs to be fixed.

My respect for Andy has gone up a few notches with this. Look, using steroids and/or HGH is deemed illegal, and now Andy Pettitte will forever be known as a cheater. But he will also be known as someone who admitted he made a mistake instead of blustering that he never used HGH (like Marion Jones).
To my knowledge, three of the people implicated in the report have now admitted it is factual: Andy Pettitte, F.P. Santangelo and Gary Bennett.
From the Mitchell Report:

McNamee began serving as Pettitte