+1 for a strikethrough button. I find it cumbersome to have a todo list built in a tree, where as it's quite simple to make a bulleted list and then just cross things off as you finish them. That is, if there is a short cut for crossing things off. Because there isn't, I never want to take the time to open up the font menu in order to select strikethrough, it just takes too long. And of course as already mentioned, it's already on the Windows version, why not keep the UI's consistent across platforms?