almost a certainty? let's look at some past years
2012 London Olympics, 27:30 farah
2011 WC Daegu 27:13 jeilan
2009 WC Berlin 26:46 bekele
2008 Beijing Olympics 27:01 bekele
2007 WC Osaka 27:05 bekele
2005 WC Helsinki 27:08 bekele
2004 Athens Olympics 27:05 bekele
2003 WC Paris 26:49 bekele
2001 WC Edmonton 27:53 kamathi
2000 Sydney Olympics 27:18 gebrselassie
1999 WC Seville 27:57 gebrselassie
it seems that the race is only fast when you have a dominant 5k-10k runner in the race such as bekele or geb.
as we don't have any dominant runners other than farah who is a kicker, farah will win, probably in 27:20 or slower.
Rupp will not need to beat his PB to be competitive, and pretty much nobody in the race will set new PBs.