Blender as a professional 3D tool?

Obviously before spending thousands on tools like Maya you may wonder if there is anything there that is free and comparable...

Blender since version 2.5 (and 2.6) made HUGE improvements and should be considered a professional tool for 3D artists.

Watch these videos (published 3 years ago):

"Completed only using open source tools in a Linux environment. Blender is the only tool mainly used for production. Only other tool used was GIMP for texture creation. Post production and editing also done inside blender.The renderer is blender internal renderer."

full render 3D office:
http://vimeo.com/12198312
http://vimeo.com/12202062

It took them 70 work days for team of 6 people, 40 work stations, 45 render blade units. They rendered 11,500 frames and cut it down to 7,500.