Update: Sorry for jumping the gun on this one. You can find Kindle for BlackBerry 10 available in BlackBerry World at this link. It is an Android port but it works very nicely.
Rejoice, all ye book nerds! BlackBerry 10 scores another big-name app to further close the “app gap”. Amazon’s full-featured Kindle app is now available as a free download from BlackBerry World. Offering personalization features such as adjustable font size, screen brightness, and background color, the app also includes touch-hold word lookup, full-sync bookmarking, and French language support. BlackBerry’s blog notes that it may take up to 24 hours to appear in the storefront, so be patient. Inside BlackBerry Blog – Amazon Kindle