I do cover mine. I have three cats and one is into everything. I have a vinyl cover, bought at JAF's then throw a cloth cover over the vinyl. My complication is the kitty pans are in the next room and there is so much dust kicked up. My machine is older and some of the parts are getting hard to find so I tend to be extra protective mostly... I do need to get into the habit of unplugging!
Congrats on your Juki 2010, I would love. love to have one! Maybe someday...