In my experience saying ANYTHING about a beautiful woman's looks is a sure fire way to get blown out. I've gone out with plenty of tens, and the one thing that every one had in common was that they wanted to be known for something BESIDES their looks.
For instance, this one ten I know loves to cook. On her myspace she has pictures of the meals she's served. She gets men emailing her ALL DAY LONG about how hot she is. If I were going to open her, I would say something that was food related.
For instance, I would weave a story about how I was hosting a dinner party on Friday, and I wasn't sure if a Syrah or a Pinot Noir would be a better match for the meal. Then I would go into luscious detail about what I'm serving, and finish the email with a question about what she would server in a situation like that.
An opener like this is perfect because it ignores her looks entirely, appeals to her self-image as a more than a pretty face, it DHVs you big time, and also implies that you have a couple of bucks without spelling it out. Best of all it's a re-usable opener so you could cut & paste it for the next ten you find
How to Date Tens You Meet Online : The Folsom Method