I kind of like the looks (barring that slide effect, which, as other people said, is pretty ugly and distracting). I find it very weak in terms of marketing, and both professional and enterprise options lead to the same page. Yeah, I know it's not the same, but since it looks exactly the same, most people will think they clicked the wrong link or that you have the wrong link, nobody will care in checking URLs nor content.
I like the "Standard" page much more than the others, but again, poor marketing. That "out of the box" arrow should lead to info, not to a form. Where it says "Features" I'd hope to see.... features. Not just marketing text. And all those tabs leading to "contact us"... well, they're simply leaks. If you have a tab with a link to some specific feature, I expect to see that feature explained, not a "contact us" form. Chances are many people will back off from it and they will never know why your product is better/different/whatever nor they will contact you to find out. The message your site screams right now is "we're afraid that you won't be convinced if we show you our product, so contact us so we spam your ass off" . Not saying that you'll do that, just what many people will think.
on the professional and enterprise pages, you have the content, which is way better, but it's as if you're afraid of showing it again. That big gray thing makes everything confusing, I don't know what I should look at, the tabs in the body are not clickable even though you have an arrow (which always means "continue" or "see more", not "end of the road") and the top bar really, really, REALLY needs to stand up with a different color. If you're afraid of color, at least use black, or dark gray, or something absolutely different to the rest of the page, not "camouflaged" within the page.
Again, all in all I like the look, but you'll need to ask yourself if you want to have a pretty site or if you want to sell. IMHO, of course, I might be absolutely wrong
