Saving $25 is more important than getting exposed to Ads.
Amazon launched a new lower priced Kindle eBook reader in April. The new Kindle with Special Offers sells for $114 instead of the $139 the standard Wi-Fi Kindle is going for. For the saved $25 you get exposed to ads on the Kindle. Kindle special offers and sponsored screensavers are displayed on the Kindle screensaver and on the bottom of the home screen. Amazon mixes in special offers to make the ads more bearable.
I was not sure if anybody is going for this deal, but apparently Kindle customers love it. The $114 Kindle with Special offers is the best-selling Kindle. Amazon touts since, I think it is already years, that Kindle is the best-selling product on Amazon. Now the cheapest Kindle is on top followed by the $139 Wi-Fi Kindle.
Amazon is also likely to launch a Tablet soon to compete with the Apple iPad. Given the success Amazon has the advertising supported Kindle, I would not be surprised if Amazon is also going to offer a Amazon Tablet with special offers at a budget price.
More details about the Kindle can be found on Amazon.