Frightening bugcounts in commercial software

http://lwn.net/Articles/115530/ "Commercial software typically has 20 to 30 bugs for every thousand lines of code, according to Carnegie Mellon University's CyLab Sustainable Computing Consortium. This is equivalent to 114,000 to 171,000 bugs in 5.7 million lines of code. " What!? That seems like a ridiculously high number. Can it really be true? Would be interesting to see bugcounts for respective languages and years rather than having it all lumped together. About Linux "Our findings show that Linux contains 0.17 bugs per thousand lines of code, which is an extremely low defect rate and is evidence of the strong security of Linux. Many security holes in software are the result of software bugs that can be eliminated with good programming processes." And Linux is written in C right? So the massive bugcounts in commercial software can't all be blamed on malloc and free...