Get it All

Summary:  Returns the number of blogs that exist on either the current domain or the domain $id.

Detail:  This function counts the number of blogs on a give domain.  By default, it checks the current domain, but if $id is set, another domain can be checked as well.  The number of blogs is cached in the dB for 60 seconds, but queries after that 60 seconds elicit another query of the dB.