Apple released today a new browser (yep, add another browser to check for bugs to the list) and the user agent is:
Mozilla/5.0 (Macintosh; U; PPC Mac OS X; en) AppleWebKit/48 (like Gecko) Safari/48
The official name is
Safari and is a beta version.
It is based on the Konqueror engine.
Please take note, this is a new human browser, not a bot.
:)