Unlike Amazon's policy with Kindle readers, you can't pay a bit extra to opt out of the ads. They're baked into that attractive $199 starting price. (What I really don't understand is why the top-of-the-line $499 Kindle Fire HD will still make you look at ads, but that's a whole different story).
Based on Amazon's official documentation for the Kindle Fire, the ads seem most likely to promote Amazon products and services like e-books, music, movies, etc. But the same documentation shows ads for third-party stuff will sneak in.
In this case, we see an ad for the upcoming movie The Words. (CNET has a screenshot of this, but I can't for the life of me find it on Amazon's site after digging around.) I'm sure other ads like this will appear on the lock screen once the Kindle Fire HD hits customers' hands.
But it gets worse. I've been perusing a bunch of hands-on photo galleries of the Kindle Fire HD and something caught my eye. Whenever you hover over an app, e-book, song, etc. in the Fire's content library, you're prompted to check out other apps or e-books or songs or whatever. Like reading Esquire? Check out GQ! Like playing Angry Birds? Check out Flight Control! Like Kanye West? Check out Jay Z! And so on...
Now is this a big deal?
I'm not too bothered by the "suggested" items at the bottom of the screen. It's very similar to Amazon's experience on the web, and they could actually help customers find cool apps and music and games they'd like to try. However, I'm sure the suggested content will really bother some people, especially since it's so different than the tablet computing experience they're used to on devices like the iPad and Android tablets like Google's Nexus 7.
But the lock screen ads do bother me, especially since there's no way to opt out of them. The black and white Kindle reader ads were never really a problem for me since they're less obtrusive than the full-color, media-rich ads on the Kindle Fire HD. It was a small price to pay for a cheap e-reader. I guarantee locking users into a forced ad-viewing experience is going to ruffle a lot of feathers, especially since Amazon's policy with other devices allows the customers to opt out.
The good news: This could be a very simple fix for Amazon. A software update to the Kindle Fire HD would allow users to "buy" their way out of ads forever. The question is whether or not Amazon will budge and provide Kindle Fire owners with a better user experience if they want it.