decided to add /apps to amazon.com and was rewarded with a list of 48 Android apps and their pricing! You need to be logged out for the Android apps to emerge, otherwise your personalized recommendations will appear instead.
You can't click through to any product listings, but that's not really the interesting bit: the prices are visible, and they're different from the Android Market. In many cases the Android App Store seems to be cheaper, and there are even some exclusive Amazon-only Android apps, such as Call of Duty: Modern Warfare: Force Recon. You can check Androidnews.de for a complete list of the price and exclusivity comparisons, or jump straight to the Google Spreadsheet. In case Amazon takes the page down, Androidnews.de also has screenshots of all the apps.
There is a possibility that we're seeing temporary placeholder data, but considering the Appstore-exclusive Angry Birds Rio is slated to be released in the next couple of weeks, and thus the Amazon Appstore must be nearing completion, the data is probably accurate.