Facing increased competition, Amazon has revamped its Kindle e-reader, making improvements all around and adding a cheaper Wi-Fi-only model. The new device is 21% smaller with the same 6-inch reading area, 15% lighter (8.7 ounces), 20% faster at page turns (with quieter page turn buttons), and supposedly offers 50% better contrast than any other e-reader. Additionally, it can last for up to a month on a single charge with wireless disabled – twice as long as before – and up to 10 days with wireless on. Internal storage has been doubled to 4GB, which equates to around 3,500 books.

There's a handful of software improvements too, such as Twitter and Facebook integration, new functions like dictionary lookup as well as notes and highlights, and it even has an "experimental" WebKit-based browser. In case you're unfamiliar with the Kindle, it's worth noting that it has access to over 630,000 paid books and 1.8 million free out-of-copyright works, and any material downloaded is accessible on iPhone, iPad, PC, Mac, BlackBerry, and Android devices via Whispersync. If you're more into audio books, it also has a text-to-speech option that reads content to you.

The premium model is priced at $189, which includes both Wi-Fi and free 3G connectivity over AT&T's network. Alternatively, there's a Wi-Fi-only model for $139 (which undercuts the Nook Wi-Fi) that doesn't have access to 3G, but can still hop on AT&T's US hotspots. Both iterations will ship to customers worldwide on August 27 in graphite or white, and case options will include one that has a built-in, retractable LED light for late night readers.