Well, here's a secret for those that meet someone on POF and claim that they've cancelled their profiles. If you do a name search for the person. If they have indeed cancelled their profile, it will list the cancelled date. If they have not, it will look as if they have no one by that name.
Zunder, the gal I was seeing said that she was going to put her search "on hold and focus on me." Okay, "on hold" is kind of vague (I could learn from this tool btw). Anyway, I cancelled my profile and discovered that she did not.
I confronted her. She said that she went through effort to perfect her profile and needed to be extra sure before cancelling her profile. I called her on her sh*t, by saying "hey we are both self-proclaimed "glass half full people' and that doesn't sound very 'half full to me.' I did this in a rather masculine and not winy type voice. She cancelled the profile and we went out for a year. Bottom line is that she was worth it (for the most part) but I probably wouldn't do it all over again because she was also flaky as well.
In fairness, sometimes women just like attention and it's nothing more. Some may not condone my suggestion, but create a profile. Look on myspace for the type of guy that you think would capture her interst (make sure that the my space profile has several photos - in case you need a few more). Send this gal a message. See if she bites. No matter if she responds or not, don't tell her you did this. Make sure that your wording is different than your own.
This will let you know if she'll admit to already seeing someone and/or if she's a wh*re for attention. Oh and by the way, don't think that I didn't have a decoy profile that didn't cater to my most recent long term girl friend. I was lucky because she this 'profile' that I created received a lot of responses, but never one from her.