The log file analysis tools will give estimate user count but you need to know how QuickPlace cache and work with proxy server. Don't just take the number from the report as the truth.
This is a sample report
http://www.boutell.com/wusage/example/summary/index.html
These are things to understand when using web log statistical reports
http://www.statslab.cam.ac.uk/~sret1/analog/docs/webworks.html
Admins, please share your methods of finding QuickPlace server utilization level. Thanks.