Music may perform better than books and other products, mainly because you can listen to the clips of an entire album in roughly 10 minutes and get a good enough feel for it without buying it to write a short review. If you have another topic that you're passionate about, great, but make sure you have a unique angle on the topic. People can get reviews about a lot of those consumer products anywhere. You need to give them a reason to visit your site.
In any case, you will not earn advertising fees for (a) any purchase that, after expiration of the applicable 24-hour window, is added to a customer’s shopping cart, purchased by a customer via Amazon’s 1-Click feature, or is streamed or downloaded by a customer, even if the customer previously followed your Associates link to Amazon.co.uk or (b) an purchase order that is cancelled or returned.
Amazon's state sales tax collection policy has changed over the years since it did not collect any sales taxes in its early years. In the U.S., state and local sales taxes are levied by state and local governments, not at the federal level. In most countries where Amazon operates, a sales tax or value added tax is uniform throughout the country, and Amazon is obliged to collect it from all customers. Proponents of forcing Amazon.com to collect sales tax—at least in states where it maintains a physical presence—argue the corporation wields an anti-competitive advantage over storefront businesses forced to collect sales tax.
It's easy to forget these days, but there was a time when Amazon didn't – and couldn't – promise that an order would arrive by a certain date. Mike helped change that. "We totally overhauled the way we make promises on the website," he says. "We got rid of the 'usually ships in 24 hours' messaging. We developed the capability to make these aggressive delivery estimates and keep them. In many ways, this was what Prime was born of."