Yes, really. You might re-read where the potential exploit was found. It wasn't in OS X, that's for sure. The rest of it is simply Zovi's opinion (he's an MS guy). Since OS X (and Linux, for that matter) are based upon UNIX, security has been an issue since the 1970s. (For example of Vista, see this Information Week
article.)
Notice, that link is a Mac source as well...
Actually, the original article was published by ComputerWorld and reprinted in MacWorld.
Not trying to start any brand war here, but to blindly assume that a Windows platform can't be secure is a very illogical approach.
No one is saying that it can't be (as in, maybe someday), but XP certainly isn't and Vista has already been exploited in the wild.
As a sidenote, I wouldn't use a "beta" browser on a production system regardless of who made it.
Nor I. No Safari 3 for me until it's been through beta.
"Raw" is not an acronym, abbreviation, nor a proper noun; thus, it should not be in capital letters.