I am using version 10.63.4 and the problem is still there, using about 48% of CPU. The usage continued after I exited and I had to nuke each of three instances in task manager.
I had a problem for quite a while on my PC where the notes pane content would disappear. I found that if I closed out of Evernote via EXIT under FILE in the menu and then restarted the program that all of the content came back (Paid account).