Most of the tech companies in the area treat programmers/developers (and IT as a whole) as a fossil fuel, to be immediately burned for their energy and quickly forgotten. Attitudes are slowly changing and quality of life is improving at a glacial pace. Still, it's a hard market to thrive in-- long hours, pay that is commonly bottom 25% of national medians, and special types of business people that can only be the result of inbreeding. Expect to be worked like a rented mule, especially in the health care sector.
STL does have its gems (Enterprise RAC, Savvis, Panera, MasterCard etc.), but they're pretty difficult to get in to with all of the competition.