Actually I am thinking of jump ship from Canon to Nikon too... and if that happen, D600 will be the first Nikon cam I will get... but the oil splash issue really stay my hand, and until that issue is solved I will not jump in.
(Oh... btw, having used Canon extensively for the past 2 years, I dare say that Canon's camera do not have oil splash issue (at least mine didn't and I didn't hear any issues from many of my friends too) and I owned and used 1000D, 40D and 7D, and I have experience with 550D, 600D, 60D and 5DmkII... so far none show any oil splash issue... dust issue - yes, and I think that is normal.)