Anup, commenting on an earlier post here, points me to Morgan Stanley's oil outlook:

We think that the current correction, although probably calling for some reversion in the winter season, is the beginning of a structural change in the market that should bring crude quotes down to around $50 in the next two-to-three years, if not significantly lower.

They cite both demand (a housing-led slowdown in the US), a lower risk of hurricanes, and supply increases of 1m b/d in both 2007 and 2008, along with increased refinery capacity and increasing investment in alternative energy sources: they don't even need to forecast a recession to justify their call!

Chalk Morgan Stanley up in the "OPEC is powerless" column, I guess.

Have Oil Prices Peaked?