The biggest thing is to verify that the guy contacting you is the same guy from ECCIE. JoeBlow1234 on the phone or
JoeBlow1234@gmail.com isn't necessarily JoeBlow1234 on ECCIE.
Exchange a PM (Private Message) before you believe it's really JoeBlow1234. Also watch out for similar names, such as JoeBloe1234 or JoeBlow124
As for long time ECCIE members with no posts, the long history probably improves the odds a bit. Sometimes, a bad guy will have a long running ID, but most of them don't. A long posting history improves the odds a bit further. Most of the bad guys are spur of the moment things, but some are more organized.
There are some ladies' private discussion areas on this board.
http://www.eccie.net/showthread.php?t=1201257
Don't put too much faith in screening, anyway. Always be careful. Realize it does cost you some business, so weigh the risks and benefits, and the level of screening you do.