We're all track people here--but for non-track people, Bolt IS track and field. There is nobody else.
There was no way Bolt would be exposed during either the olympics or the subsequent WC's--he was the goose that laid the golden egg.
Unlike the Ben Johnson era, track is really big money now, for a lot of people. More people have more invested in track, and therefore in Bolt.
I doubt they'd bring Bolt down anytime soon, which is what is puzzling. If he WAS using in '08 and '09, and wasn't caught, why not use again? They wouldn't bring him down now, unless they had someone else golden to replace him with--and they don't. He's marketable, and nobody else is--they are either a-holes, wooden, lack personalities, tainted, ugly, or just plain dumb.
There is no other poster boy, so I think Bolt could use right now without any fear of being exposed.
So why are his times crap compared to what they used to be? Either he IS using and still failing, or he is NOT using and failing.
I think his failure is due to more to weights, aging, biochemical changes, loss of flexibility, laziness, etc. than to a lack of drugs. In my experience, tall people can do some amazing things when young, but they don't last--especially at weight-bearing activities like running. They break down faster, unless they are really thin. I don't know, just my opinion.
I'm still sure that no matter what he does, we will never again see 9.58 in our lifetimes--unless he goes really insane and does lines, a la Sotomayor.