I wish you'd have sub-divided the 'Yes' votes...
... to [Yes (lots)] and [Yes (a few)] -- I mean, if the number of Linux viruses tripled, we'd get to what... 1 a year? I think there will be an increase, but not an alarming amount... Because of this fact, I did vote Yes, but I don't see this as "the end of the world."
It's human nature to "not fix what isn't broken" and I think a lot of the viruses for Linux that may be created in the future will not target the latest-n-greatest kernel, but concentrate on older vulnerabilities that people don't patch for. For this to be "cost effective" for the virus creators, there has to be a "critical mass" of Linux machines already (which *might* happen in the next few years) and then wait for these individuals to ignore the patch manager. It's also possible that the virus creators could target embedded machines (routers, wireless APs, etc.) that would not be patched on a regular basis -- there are a *lot* of those machines out there now.
And there are very secure closed-source operating systems out there - I don't believe there was ever a virus written for VMS, for example; and there were a *lot* of VAXen installed at one point in previous history... [[ Yes, I still have a couple in my basement... ]]
