MartinH.

The documentation is... less than optimal. The website/wiki can be confusing. Feature sets are not exactly stable (new features require code changes that sometimes break old scripts or features that existed in past versions are lost). Overall stability varies between versions.
The 3d industry was using commercial programs ever since because they existed long before blender was usable (I remember a time where it didn't have an undo function yet). When and why should they suddenly decide "hey, let's all throw our years of experience with commercial software xyz into the bins and start learning this badly documented free open source tool."?
Not very likely I'd say...
This might change over time with people getting started in the 3D industry as freelancers or small startups that start out with blender knowledge instead of commercial app knowledge. To people just wanting to learn 3D stuff for themselves Blender is very attractive since it's free and has a growing feature set.