Yesterday, Apple stepped up its criticism of the Windows operating system.

During the keynote addresses at Apples WWDC (Worldwide Developer Conference), Apple executives took few potshots at its rival Microsoft. Bertrand Serlet, senior vice president of engineering for Apple, chided Microsoft for "photocopying" earlier features in Mac OS X into the current beta release of Windows Vista, even accusing the Redmond software giant of borrowing Apple's Aqua user interface logo as part of its own new logo for Windows.

"If you can't innovate, you have to imitate, which is never quite as good, " he said.

Apple CEO Steve Jobs echoed those sentiments, claiming Microsoft developers spent more time chasing innovation at Apple and Google than creating some of their own. He said he was so concerned about Microsoft copying new features in Leopard that he was not presenting many of the more "amazing" new things in Leopard for public view.