CTRL looks weird as the chars don't fit the 26px width of the key, making it a multiline.
Making it one pixel wider, resolves it on my machine. Ctrl fits nicely.
I was able to repro this in Chrome 21.0.1180.57 OSX. I added white-space: nowrap as Tim suggested and verified that it doesn't mess up other browsers. The change will be in the next prod build.