In a recent article, Matt Rosenberg of About.com lists more than thirty (count 'em!) branches of geograhy including Geographic Information Systems.
Geographic Information Systems
"Geographic Information Systems or GIS is the branch of geography that develops databases of geographic information and systems to display geographic data in a map-like format. Geographers in GIS work to create layers of geographic data and when layers are combined or utilized together in complex computerized systems, they can provide geographic solutions or sophisticated maps with the press of a few keys."
Branches of Geography
Others include Economic Geography, Transportation Geography, Applied Geography, and Quantitative Methods.
I don't see a specific branch for Business Geography but it might fall under Applied Geography or perhaps a bit of Population Geography and Quantitive Methods depending on what specifically is involved.