[swivelmaster]

IMO phone screen (if it really is a "screen" and not a full "interview") should be fifteen minutes or less. I usually ask a few very specifically CS101 type questions to see if they remember any of it, and if they don't, they don't come in for an interview.

[spaghetti]

I agree about the phone screen length. Whether you call it an interview or a screen it can probably be much shorter than hour with almost all of the benefits.