As the linked article states, Armstrong has always denied using any kind of banned substance while competing, but if he is found guilty of the charges, he'll face a lifetime ban from the sport. That doesn't seem to be an issue however, as he retired from competitive cycling more than a year ago. He is immediately banned from competing in triathlons however, a sport that he has recently taken up and has been quite competitive in.
The USADA says that it has blood samples from Armstrong dating back to 2009 and 2010 that show the signs of of potential doping. The indicators are that Lance could have potentially used EPO or undergone blood transfusions in an effort to increase performance. It should be noted that over the course of his career, Armstrong has been tested more than 500 times and has never once tested postivie.
These charges also come after the U.S. government dropped its investigation of Armstrong a few months back. At the time, it seemed that that would put an end to the story, which had yielded little results and cost millions of dollars. Now it seems that Armstrong isn't quite out of the woods just yet.
I'm sure we'll hear a lot more about this story in the next few days. It should prove interesting, although potentially very disheartening, for fans of the sport. Stay tuned!