Scoble writes on Google+:

So, let's cover the price, first of all. I bet that Larry Page is considering two price points: something around $500, which would be very profitable. Or $200, which is about what the bill of materials costs. When you tear apart the glasses, like someone else did (I posted that to my Flipboard "Glasshole" magazine) you see a bunch of parts that aren't expensive. This has been designed for mass production. In other words, millions of units. The only way Google will get there is to price them under $300.

I wouldn't be shocked if Larry went very aggressive and priced them at $200. Why would Google do this? 

Easy: I'm now extremely addicted to Google services. My photos and videos automatically upload to Google+. Adding other services will soon be possible (I just got a Twitter photo app that is being developed by a third party) but turning on automatic uploads to other services will kill my batteries on both my phone and my glasses (which doesn't have much battery life anyway). So, I'm going to be resistant to adding Facebook, LinkedIn, Twitter, Evernote, and Tumblr to my glasses. Especially when Google+ works darn well and is the default. 

Also, Google is forbidding advertising in apps. This is a HUGE shift for Google's business model. I believe Larry Page is moving Google from an advertising-based company to a commerce based company.

The first thing I tried that it failed on was "find me a Sushi restaurant." I'm sure that will get fixed soon and, Google could collect a micropayment anytime I complete a transaction like reserving a seat at a restaurant, or getting a book delivered to my house, or, telling something like Bloomingdales "get me these jeans." 

There is literally billions of dollars to be made with this new commerce-based system, rather than force us to sit and look at ads, the way Facebook and tons of other services do.

I agree that $200 is the mainstream price point.

"Also, Google is forbidding advertising in apps. This is a HUGE shift for Google's business model. I believe Larry Page is moving Google from an advertising-based company to a commerce based company."

So Google Glass will be the equivalent of Kindle?

Pretty much. But instead of books it sells other kinds of commerce. 

A commerce based business model?  Interesting...that is a pretty big shift.  I'm not a big believer in advertising biz models.