I agree with Bill--use just one space after a period. But, we're using selective rules to justify our use of a single space.

If the reason to use one space is that we shouldn't be constrained by old fashioned type rules in our digital typeset age, why then do we follow the age-old rule of putting periods inside quotation marks? There isn't much of a chance of that digital period breaking off!  

We're all a bunch of subjective ninnies!