robinturner | It's me

To my relief, I have found confirmation from an impeccable source that "It's me" is correct and the pretentious "It is I" violates the rules of normal English usage. Of course that doesn't mean you can't say "It is I" or "He is taller than she"; it just explains why they sound odd. Here's the straight dope:

Putting aside some well-known complexities like coordinate subjects and also putting aside a slew of normative prescriptions, the basic rule for nominative/accusative choice in English is: nominative for subjects of finite clauses, accusative otherwise. This rule has to be understood literally: only subjects of finite clauses; things understood, or interpreted, as subjects of such clauses don't count. So free-standing pronouns are accusative, even when they're interpreted as subjects: Who did that? Me. (Arnold Zwicky, posting in Language Log.

While I'm at it, here's yet more ammunition for one of my favourite linguistic causes: "Singular 'They': God Says It, I Believe It, That Settles It." And if any prissy EngComp teacher says "Oooh, there's a comma-splice in that title!" I shall beat them around the head with an asyndeton.