Those dots represent space characters. You will also see little arrows for tabs, and little hooked arrows for carriage returns.
Press CTRL + R + W to toggle the dots you're seeing.
BTW this is a standard Visual Studio feature. It has nothing to do with CodeRush or any other plugin.
EDIT As Martin points out, you could press CTRL + R, then CTRL + W. Personally I press CTRL then hold it down for the R & W keystrokes. It's less typing.
Drew Noakes
2009-10-06 13:16:55