welcome. The website has a clean design and is certainly focused right in there to registration. However, here's a few thoughts I had:
From the homepage alone, I don't know enough about it to just give my email address and be signed up. Registration is free for the Beta (which is only explained on another page), but are there any other fees?
What happens when I give you my email address?
I see the screenshot on the homepage -- that's really good -- but are there any demos, videos, or other screenshots?
Is there documentation? I would want to know how easy it will be to add this feature to my app. What does the code look like that I have to type?
I suppose I just don't know enough about it to sign up. I like that email is the only thing required to start using it, but because I don't know what the next step is, I hesitate to even sign up.
I would suggest putting much more content on the site. You'd be interested to see how Betterment and SquareSpace do it, for example. Both have examples/demos and lots of content. They have a big, obvious "SIGN UP" button that takes them to a neat little form. The button and form describe what exactly is going to happen.
You definitely want to focus on those SIGN UP buttons, but you also have to provide details to users who are looking for it. For example, on your homepage you could add a video, or introduction to the features, or testimonials. SmartyStreets, for example, lets you dive right into what they do from the homepage (disclosure: I designed that site).
Have auxiliary content pages which describe the what-why-how of your product. This way users can feel secure knowing it is well-documented and supported. Even if they don't read it all up front, they'll know it's there if they need it.
I realize the site is new, but now expand it. Add more to it -- but keep it clean and don't force users to drink from a fire hose! Expose them to more and more, keeping the focus on those SIGN UP buttons (or the form, whatever). Make them available almost everywhere potential customers will "hang out". Good luck! Hope this helped.