Q about "exact" match counts?

["Gaulin, Mark" <mg...@globalspec.com>]

Hi 
I was wondering if nutch returns exact match counts or estimated match
counts, or if this behavior was configurable.  The reason I ask is that
on a very large index I'd rather get the top 10 results right and get
them quickly and not spend time getting the total number of documents
that match exactly right. (I assume that's why Google reports totals as
"1 to 10 of about 1,000,000")   Is this something that nutch/lucene can
do?
Thanks
	Mark