Mike Sando of ESPN talked with 42 league insiders of the NFL, ranging from coaches, general managers, and offensive/defensive coordinators, and asked all of them to put each NFL quarterback into one of five tiers. Sando then averaged the ranking across all 42 opinions, and published them here (ESPN Insider required). Surprisingly, Saints QB Drew Brees was not in the top tier list of Quarterbacks, coming in the second tier, #5 overall.
Here are the definitions of the tiers:
Tier 1: Can carry his team each week.