If you look at the USAF's "Roadmap for UAS 2009 to 2047" you will see that they want MQ-L for KC-X. MQ-L is an unmanned version of X-48; Boeing's BWB offering.
Sorry to BEagle if you've just choked on your cornflakes!
iRaven
PS. MQ-L is also looking replace RJ, B52 and AWACS around 2025