Inc. Magazine, (not to be confused with Forbes and related threads), has released their Top US Cities for doing business in 2005 (//%22http://www.inc.com/magazine/20050501/bestcities.html%22). They looked at 274 metros. Tulsa rates a mediocre #186 in "Best Places Overall", and a poor #258 in "Fastest, Most Sustaned Growth", but get a #3 in "Most Balanced Economy and Growth".
Joel Kotkin headed up the research.
The best explanation I can find for this is that our employment is balanced nicely across all sectors, compared to lower ranking cities.
http://www.inc.com/bestcities/2005/sector_search.html?city=tulsa&state=&year=2005
Either that or Kotkin wants to get invited back for another lecture[;)].