Release: 2.41 [16 Oct, 2015]

New Features

Edit Book: Allow editing an unzipped EPUB (a folder) as a book
Useful if you wish to store your ebook in a version control system and edit it directly with the calibre ebook editor (File->Open folder as book)

Edit Book: Allow easily removing items from the popup menu for the 'Insert tag' button
Make Tag Browser more useable with keyboard shortcuts. Configure the keyboard shortcuts in Preferences->Keyboard->Tag Browser
ToC editor: Add context menu item to change selected entries to upper case
Bug Fixes

Edit Book: Preview panel: Render in XHTML mode. Fixes svg elements using a global svg namespace not rendering.
Tag Browser: Fix clicking on first-letter groups for series not working
DOCX Output: Ignore corrupted images in the input instead of erroring out on them.
E-book viewer: Fix keyboard shortcut to toggle table of contents not working when ToC window is made floating.
Closes tickets: 1503910

Allow ebook-metadata to work with read-only files when no options are specified to change metadata.
Closes tickets: 1504345

Tag mapper: When the replacement tag contains commas, create multiple tags instead of replacing the comma with a semi-colon.
Closes tickets: 1503526

HTMLZ Output: Set the HTML <title> to the book title.
Closes tickets: 1502592

Improved news sources

Boston Globe
Wall Street Journal
Komputerra
Spectator Magazine
The Independent