We had this "battle"
before....
Sandman, if someone has in the past said to you that Macs are not susceptible to problems, whether it's bugs or malware, they were seriously misinformed. Of course there are bugs in Mac OS X, of course it happens that Macs crash. Whether there are fewer bugs in Mac OS X 10.5.2 compared to Vista, I don't know. But remember that 10.5 came out in October and Vista was launched early last year.
Being rock-solid and stable doesn't mean no bugs in my mind. It's not an absolute measure, it's relative. If we have an absolute measuring-stick, and rock-solid and stable means 0 bugs, then is any system in the world truly rock-solid and stable? Or where on the scale does rock-solid and stable start?
Concerning one MacBook Pro freezing during a demo, that could have many very natural explanations, like bad RAM, for example. Drawing any sort of conclusions from one computer is just not very useful.