The imp fills a technological gap for any inventor who can build a neat physical device, but can't make good web-enabled software.
Not exactly. At least not according to EI's web site.

The manufacturer would still need to develop their own UI and related software, but EI's web-based tools may make this easier for at least the web-based front-end. I believe the larger benefits come on the hardware end and they're covered on the site...
Lots of good information and explanation of what the EI product/solution offers:
http://electricimp.com/manufacturers/It's somewhat compelling from a manufacturing perspective and it's good to see that this page does a good job of explaining a lot of questions I had when the project was first announced.