I have to say, I like the fact that "incoming calls only" is an option I can select from the website. If I ever lose my phone again, that's the first thing I'll reach for.
But more than that, I like the fact that "outgoing calls only" can be selected right alongside it. Check 'em both, and your phone either does or does not allow incoming and outgoing calls. I think it's a glass-half-full/glass-half-empty situation, and we can see if AT&T is generally positive or negative by their response to this test.