Windows developers are abuzz with leaked news of unnannounced extra features within Apple's forthcoming Leopard operating system.

A report on a Windows Vista developer community website explains a number of features that seem likely to debut in the new OS. It describes twelve previously unknown features that are of specific interest to developers. All twelve are described as being present in the beta version of the OS which was given to developers this week at Apple's Worldwide Developers Conference (WWDC).

However, developers who attended WWDC and received their beta copy of the OS will have signed an agreement not to discuss it, which means the claims on the Windows website will have required that agreement to be broken, if indeed the claims are true.

A number of features are listed, with developers most excited about claims for "resolution independence".

"Leopard will feature a resolution-independent user interface and there are several functions to get the current scaling factor and apply it to pixel measurements," the report claims.

Resolution Independent UI can be used to provide the user with either detail (more pixels per point, but fewer points on the screen), or real-estate (fewer pixels per point but more points on the screen).

However, this feature may not be so new after all. Apple has published notes relating to Mac OS X 10.4 Tiger, notes which describe a resolution independent UI in the OS.

Additional Leopard features that have been claimed include: Address Book gaining the capacity to share accounts; a new user interface to Automator; developer tools to let developers exclude unimportant data from Time Machine backups; the capacity to integrate iCal data into third party applications; systemwide grammar checking; direct access to Raw files in Core Image and many more.