Those activities (phishing, keylogging) work because, like it or not, there are enough people using the internet who are not "computer people". Would you trust your parents to secure their computer? Your neighbor? The clerk at the grocery store? Any one of these people could be playing WoW, and susceptible to account compromise.

In a perfect world, we would all be technically savvy enough to protect our computers and data. However, it's not a perfect world. And we all have to deal with the consequences of that. Blizzard has no way of determine who is and who is not capable of securing their computer.

As this discussion is about Blizzard's authenticators and the security of your WoW account, I am going to choose to ignore your irrelevant conclusion regarding total system security.

I am neither opposed to, nor in favor of mandatory authenticators. On a voluntary basis, I am of the opinion that you are not doing all that you can to protect your data and WoW account if you do not have an authenticator. Even though I was at low risk of compromise I chose to get an authenticator. Prior to getting the authenticator I was already:

1) Running a Juniper Netscreen SSG-5 appliance at the edge of my home network. It has the Anti-Virus, Deep Inspection and Web Filtering features enabled. They are all configured and active. My screening and policy rules are restrictive.

2) My OS and all applications are patched and up to date. My OS choice is irrelevant to this discussion, but I do run Mac OS X. Just because there are presently no known WoW keyloggers for it today does not mean there won't be tomorrow.

3) I run AV on my system daily and against any downloaded file.

4) I do not use BitTorrent/Limewire/the current P2P client du jour for acquiring music/warez/whatever. I do use BitTorrent for downloading LINUX ISO's related to work, but they are AV scanned and I confirm the MD5 and SHA1 checksums before use.

Even with all of that, I chose to get an authenticator.

Ultimately, as things stand today, it's your choice to get an authenticator or not. You pay your $15/month to Blizzard and you accept their TOS. If they change the TOS to require an authenticator, you will get to choose to accept the new terms, or to cancel your account.