Here’s a web video explaining the new lightbox from at aweber.
The new lightbox forms further focus your visitors’ attention on your form by “greying out” the remainder of your page until the visitor either subscribes or closes the popover form (which is easy for them to do - they just click “close” or hit the ESC key on their keyboard).
We’ve seen examples of this form in action (and the results they produced) at marketing conferences that we attend, and wanted to offer you the same ability to focus subscribers on your signup forms.
Video: Build Your List Faster With a Lightbox Web Form - Email Marketing Tips on the AWeber Blog
short but nice information about the lightbox web form