But without enough evidence, I wouldn't say It's Linux's unstablity caused machine halt. Because most machines just work fine. I think the present Linux should be stable enough for commercial purpose. Currently many ISPs have already chose Linux as their main unix type webhosting server (e.g Godaddy, I bet they have more than several hundreds Linux server. )
Compared with other unix type OS, Linux has much more bigger user and developer group. The good thing about it is Linux support much more hardware resource than other unix, because there are so many people writting driver on linux. That means you have more options to choose. The bad thing is not all the drivers are well develop/tested. So if unfornately you made a bad choice, it's reasonable the system is not that stable. On ther other hand, some other os ( like Sun solaris?) they can focus on a much narrowed hardware list.
Compared with other unix type OS, Linux has much more bigger user and developer group. The good thing about it is Linux support much more hardware resource than other unix, because there are so many people writting driver on linux. That means you have more options to choose. The bad thing is not all the drivers are well develop/tested. So if unfornately you made a bad choice, it's reasonable the system is not that stable. On ther other hand, some other os ( like Sun solaris?) they can focus on a much narrowed hardware list.