XLamp® XP-L LED is the first commercially available single-die LED to achieve breakthrough efficacy of up to 200 lumens per watt (LPW) at 350 mA.
thats what Cree just posted on there FB page.
link to the cree page: http://www.cree.com/News-and-Events/Cree-News/Press-Releases/2014/May/XPL-intro