I think your demo should be more than an example of signup page. Quite frankly, most signup pages look the same (e.g. resizable background image, centered box with text and maybe a logo, and a call to action). Where you could really differentiate yourself (over existing similar services) is better analytics that you get from your service, and a demo of the admin panel could convey that.

So for example, show that for every signup you know: 1. Where your users come from (e.g. referer) 2. Where your users are from (e.g. geo location based on ip) 3. User Agent, Browser, Mobile vs. Desktop etc...

This information is not only "cool to know" but also useful to understand who your potential customers are.

A few more things. In your "sales pitch", you mention your competitors (e.g. LaunchRock/Unbounce). I wouldn't suggest advertising for your competitor, and loosing potential customers to them, especially if you're value proposition is weak.

Finally, I wouldn't suggest your "call to action" to be to see pricing, that's also a turnoff. Instead, maybe you ask for emails for people interesting who want to use the beta when it's ready :P