There are some very successful services at the top of the online dating food chain. And, PerfectMatch.com has been climbing steadily into this top echelon of services.

Duet, PerfectMatch.com's 'Total Compatibility System' (developed by Dr. Pepper Schwartz, and leveraging facets of the critically-acclaimed Myers Briggs evaluation system), was highlighted yesterday in an informative press release— Men Are From Mars, Women Are on PerfectMatch.com.

According to this announcement, nearly 65% of PerfectMatch.com's members are female.  Another July 15, 2004 press release, LIFETIME Television Signs Multi-Year Partnership with PerfectMatch.com, announced a multi-year partnership between LIFETIME, a leader in women's television, and PerfectMatch.com.

Does PerfectMatch.com really have a significantly higher female membership than other top ranking online dating services? I would be most interested in seeing a breakdown of female / male membership numbers for the top 20 online dating services. Most of these services boast memberships in the 1M+ Club level with a much higher level of frequency than 'friends based' social networking services.

Recently, four online dating sites with sophisticated testing and matching systems: Match.com, Tickle.com, eHarmony.com, and PerfectMatch.com,  were singled out by the quickly rising True.com ( Millions of Singles Could Be Using Flawed Compatibility Tests).

Here is a graph of these five sites as currently ranked by Alexa:

There are a number of other dating services that fly at this 'altitude' of use, but these particular services all appear to put a substantial amount of due diligence into their testing and matching vehicles.