Market Cap of Each Category

The following chart compares the market capitalizations of the companies in each category. (I've renamed several of the categories but for now have kept the same classifications).



Microsoft aside, the enterprise software vendors (led by Oracle and SAP) form the largest category. The second largest category consists of the "infrastructure software" companies. Video games, the only consumer segment that appears here, form the third largest category. The engineering and design category is even smaller.

Also interesting to note, aside from video games and some portion of Microsoft's product line, there is almost nothing here that would count as a consumer software segment. Most of the big companies who write software that consumers use (Google and Apple and AOL, for example) essentially give the software away for free and make their money elsewhere (advertising, content, services).