I started getting emails from Facebook, because someone had used my work address to create an account. (I get a lot of spam on this address - it being cb@... .com)

Really, very annoying! I guess this is kind of to be expected of Facebook, though.

I'm not sure what to make of this farce, but I'm definitely not following Mike's suggestion to create a facebook account and list all my email accounts there.

You can create an account, add all of your emails, but then limit their visibility to 'Only Me'. That way people can't impersonate you, and you don't need to reveal all of your emails to everyone.

You can do this with Twitter too.

It's a tradeoff really, had they required an email validation before any actions there would definitely be a drop off rate in completing signups, especially early on when people didn't have large social graphs on facebook to pull them in.

It's not a tradeoff, but an externality paid with time instead of money. Facebook won't suffer any inconvenience, only non-users of Facebook will.

Add this to their opt-out by default when adding new features, and Facebook is becoming more and more a spam platform.