I recently took delivery of my 27" i7 iMac. I've installed MS Office and when I recently went to use word for the first time since installation, I noticed the background is divided into 2 shades of grey. Word is functioning normally other than for this but the split display is just a little distracting. I also use Word on my MBP and don't have the same issues there, nor did I on my old G5. Anyone got any clues?