Amazon is planning to launch the ultimate subscription package for book lovers. As first reported by GigaOm, the company is apparently preparing a new offering called Kindle Unlimited, which will provide unlimited access to over 600,000 titles and thousands of audiobooks for $9.99 each month. Amazon has yet to unveil Kindle Unlimited in any official capacity, but users spotted promotional banners for the unannounced service on the retailers website. It seems youll be able to access Kindle Unlimited content from any device that already supports Amazons Kindle ecosystem. …