Great article, but there is one nitpick: you need parentheses in the signature for bind. It should look like

    (>>=) :: Monad m  -- for any monad,
          => m a      -- take wrapped value
          -> (a -> m b) -- and a function which needs it unwrapped
          -> m b      -- unwrap it, and apply that function

Or, written the other way:

    (>>=) :: Monad m           -- for any monad,
          => m a               -- take a wrapped value
          -> ((a -> m b) -> m b) -- and return a function which can take an 
                           -- unwrapped value and a wrapped one and 
                           -- return another wrapped one

Which also makes the comments on the second one a bit inaccurate. It should read "return a function which takes a (function from an unwrapped value to a wrapped one) and returns another wrapped one."