The questions I have are in the title. Which is right, subject or object pronoun?
It's seems the first, "It's me/I they want!," is a reworking of "Subject + Verb + Object" to "Object + Subject + Verb" with a "dummy" subject attached. However, this sentence can also be written, "It is I whom they want." On purely grammatical terms, I believe this is correct, though you might lose a few friends talking this way.
Additionally, the "Who/Whom is it you asked?" can reasonably be answered, "It is she whom you asked." What's going on here? And which form of pronoun should guide statements/questions like these?