This could definitely be a classic race. What makes the event particularly interesting is that both runners are racing a distance that historically/statistically has not been their bread-and-butter event, although some would argue that since Lagat has a 7:29 3000 to his name that it is his 'bread-and-butter' even when really everyone knows that the majority of Lagat's career was focused on the 1500m/mile, becoming the second fastest 1500m runner ever (3:26.16). He's never going to come anywhere near that same accalade for the 3000m or 5000m. As for Rupp, he seems to become a more efficient runner the longer the distance he races (compare his 13:06 to his 26:48). And yes, even though Rupp has just run the AR for 2 miles indoors (8:09), which converts to somewhere around 7:33/34 for 3000m, everyone knows the 3000m is not his "bread-and-butter" event. That being clear now to any letsrun posters who want to gripe about small petty argument, I think that it will be interesting to see how both these runners fair at this distance.
So Rupp averages 61's for 2 miles while Lagat averaged 63's for 3.2 miles. Lagat also recently ran a 3:36 1500m, which is equivalent to 58/59 seconds per lap, but Rupp also ran a 3:57 mile in early February so he's capable of running 59's as well. I still think that Rupp's speed is getting faster each year and that he is closing the gap on Lagat. I think that if Rupp can stay relaxed, hang on to Lagat's shoulder, as opposed to letting Lagat hang on his shoulder, then Rupp should have a decent shot at beating him.
I give Lagat a 59% chance of winning
I give Rupp a 39% chance of winning
I give anybody else in the field a 2% chance of winning