It doesn't make you look like a slut at all. If anything, fashion conscious and most guys appreciate that in a girl.
Now, wearing that on a first date may be a little tricky. I don't know about this guy that you like but most of my friends and I don't like something as laid back as a movie for example. We like something engaging that both the girl and I would have fun in. if you wanna be safe, think of yourself in the guy's point of view, how do you think he sees you? If he's creative enough, he'll probably think of a date that'll match what he thinks of you. Besides, I think the dress is too gorgeous for a movie or coffee, he might think you're trying too hard.
I'd recommend dressing a teensy bit nicer than you normally dress when you are around the guy. If you normally dress in a similar manner to the girl in the picture, then I think it'd be fine if you went ahead and dressed like that, because the guy would know that you are normally into fancy fashion stuff. If you normally wear a shirt and jeans, I'd stick with something like that, or maybe a simple dress.
Okay, just my opinion but the outfit might say "high maintenance" more than anything. It looks expensive, you'd probably be over-dressed for the date and that could make him uncomfortable (guys have fashion feelings, too!). Uncomforable feelings are what you want to avoid on a first date! After his initial "woah, she's gorgeous" reaction it could get him thinking that maybe you're not quite as down to earth or "right" for him as he originally thought.
However, if he takes you to his corporate holiday party, it would most likely be appropriate attire for that type of venue. I'd wait and see where he wants to go before buying the dress.
Let me say that if you want to appear classy, most men find a pair of nice slacks, kitten heels and a dressier shirt quite appealing. (Like The Editor pants at Express. They often have the Editor cut in a fancy denim fabric that you can dress up and down.) Often times this will send the impression that you can take care of yourself, you are independent and someone worth getting to know. You're on the right track but if you want to slightly over-dress I'd go in the 'professional' direction instead of the 'prom-ready' direction. Gorgeous threads, though!
It's not slutty but it's a bit much for the first date. Wear jeans and a cute top. Save that for another event.