Well, Im not sure if oil needs to be at $100/bbl to stay afloat. Even the Saudi's said a few months back that it should be in the $80 range, which is still probably pretty high.
That $100/bbl is only more $ for opec and the speculators. No one else (other than governments collecting taxes) benefits from that high price. It is infllationary, and it is at the core of the current downfall of the world economy. (well, the crooked real estate lenders helped a little too)