Worth Less Than You Save

I saw that $114 ad-supported Kindle over the weekend, and couldn’t decide what to make of it.

If Amazon really is trying to get Kindles into as many hands as possible, then a $25 savings on a $139 product seems too little. But the other question I have is: Is $25 the most Amazon can get in ad revenue for a device people will stare at for 15-60 minutes a day, for one or two years?

That seems undervalued to me.