Guys, it's possible Woods took meds or a combination thereof that he didn't realize would affect his driving significantly. He was pulled over when they found him, not actively driving. Playing the devil's advocate here, but let's see what facts come out in the legal system before condemning him as the spawn of Satan perhaps? I think it's likely he messed up big time, but things do happen.
The comments about him hiring drivers to taxi him around are spot on though I'll admit, especially after this point, there's no reason he shouldn't be doing that.
Edit: Just some personal experiences where people claimed certain drugs (say, Gravol, things like that but it applies to any prescription drugs too) did them right and they had no after effects, whereas I tried them and was wiped out completely for a day afterward. Drugs affect people differently than others, I'd like to see the evidence from an investigation before passing judgment.