Amazon announced today that a new update for its Kindle e-book reader brings two significant enhancements. The company has timed the introduction of these new features perfectly to influence holiday shoppers who are undecided between purchasing the Kindle or a competing gadget, like Barnes & Noble's Nook.

With the latest firmware version, the Kindle has an 85% longer battery life, which is quite an improvement. The device can now last for up to seven days on a single charge with the wireless turned on. Additionally, the Kindle has finally received a native PDF reader, something customers have been after for a while. With built-in PDF support, users can simply transfer the files via email or locally through USB, rather than having to covert them.

The company took a moment to brag, saying the Kindle is already the best selling, most wished for, and most gifted product on Is the Kindle or another e-book reader on your shopping list?