This is actually a REALLY great shot... i remember watching this on TV... i'm quite surprised it didn't do better!
I might make a slight suggestion... to make the image "appear" sharper than it is you can "legally" cheat... make a separate layer including just the background (do a VERY neat job of this) and do a VERY VERY tiny gaussian blur... just to make a slightly shallower DOF... EVER SO SLIGHTLY... then re-size it with the long end at 1600 (twice the max) then sharpen the layer that shows the skaters... click on "filter" - "Sharpen" - "Sharpen"... sharpen it twice... yea... too sharp... that's good for now... then re-size it to 800 on the long end, and it won't be too sharp any more... it will ne just right...