Digital Book World has added a release about Vellum’s ebook creation software for OSX. From the article:
Authors who want to create their own digital books are often frustrated when converting their manuscripts into ebooks. A Seattle software company called 180g has created a tool, Vellum, that handles the technical ins-and-outs of building EPUB, MOBI, and iBook files—simplifying ebook conversion and giving authors more time to focus on their craft.
Vellum ebook creation software, introduced today, runs on Mac OS X and allows authors and small publishers to easily create beautiful ebooks for iBooks, Kindle, and Nook without any prior experience or training.

Apple announced new hardware and software today, including the FREE release of OS X Mavericks available on Apple’s website