I think everyone's missing the point. For the computer masters out there, you've probably had to design a website at some point in your life so it's important to have the most popular browsers anyway for testing. For the rest of the world: everyone's responses here are crazy. Apple is giving away free software. They would only be doing this if they thought that people would like it and possibly thing "hmm, if this product is easy and good, maybe a Mac would be too."
Far from it.... yes they are "giving it away" but let me decide to check the box to say I want to download it, not have Apple tell me that I should be downloading it by checking it for me.
For the MS bashing that happens here, Microsoft only has the critical updates selected by default, you can use the Windows Update tool and only ever see the critical updates that should be downloaded, there are optional updates available but they are not security related. In the optional updates are driver updates for network cards etc.