Can You Trust the Promises of Free Personals Sites?

It seems like almost every day there's a new website advertising free personal ads. With all these companies approaching us all the time, how do we differentiate between those who are truly able to deliver their promise of “free” personals from those who are using it as little more than a not-so-clever marketing ploy?
When signing up for an online dating service for the first time, the number of options out there can be staggering. Testing the waters by signing up for a few free personals sites can be a good first step into the online dating world without committing to paying for memberships. But, how do you protect yourself from being burned by a bad first experience with sneaky companies who lure customers in with promises of 'free personals', but rarely deliver?
One easy way to find out is by signing up for a free personals service. Start the sign up process, and if at any point your credit card is asked for, quit. There are few reasons for an online company to ask for your credit card unless they plan on taking money from you. But, read the fine print. If there are reasonable motivations for asking for credit card numbers, you might be able to reconsider. Trust your own judgment because ultimately, it's your money and your decision.
Another way to gage whether or not an free personals service will deliver their promise, browse around the site. If it looks reputable and nice, and if there are a lot of members, this could be a good sign. If other members have already signed up and stayed (check for 'last online' dates or recent activity on message boards, forums, etc.) it probably means that the site has a few satisfied customers.
To sum up, be wary of online dating services offering free services. Though there certainly are excellent sites who offer their services for free, there are also a few who use the 'free personals' promise as a lure to trap unsuspecting singles.