I was trying to tell this to a non techie friend, and they just didn't get it. Microsoft has by far the biggest market share in the world with their OS, and IE is huge, but also besides the vulnerabilities, it's also a large target. This shouldn't be too hard to explain, but for some people, Microsoft is just another company no bigger or different than Apple.
Judging from all the product placements in the movies and TV, it does look like Apple has a bigger market share than they really do.
Safari is so-so, but I like Firefox and Opera.