No - the number is just an approximation.
When you perform a search, the results
are often displayed with the
information: Results 1 - 10 of about
Google's calculation of the total
number of search results is an
estimate. We understand that a
ballpark figure is valuable, and by
providing an estimate rather than an
exact account, we can return quality
search results faster.
In addition, when you click on the
next page of search results, the total
number of search results can change.
In this case, we realize that some of
the query results are duplicates, and
collapse those duplicates so that you
can find the specific result you're
looking for more easily. Collapsing
the duplicates decreases the estimated
number of results, as well as the
overall number of results pages.