digging around online its worded that they are planning on rebuilding the Beep but, they are undecided on if they will replace with another 567 or replace with a 645. She is still in the book end scheme. heres a link to wikieida http://en.wikipedia.org/wiki/Beep_(locomotive)
As beloved as the Beep is...
It is, after all, some sixtyj-odd years old and a one-off locomotive. Odds are, it will be perminantly retired and put on display somewhere on BNSF property or donated to a museum somewhere (and I'm NOT a betting man, so don't ask me where my money is).
Mind you, I would love to see the Beep still earn a living at the shops, but given the economic climate, it's doubtful.
Still, BNSF has a reputation for running older equipment, so... mayhapse they will rebuild it... stronger, better...
** Cue theme from "The Six Million Dollar Man" **