The annual Worldwide Developer Conference kicks off next week i.e. on June 11. Apple is expected to refresh MacBooks with Ivy Bridge architecture and Retina display. However, the recent spec sheet leaked online show that MacBook Pro 2012 does not include a retina display. But a few additions, including Ivy Bridge and USB 3.0, are there.

Citing contacts within U.S. Apple base, a forum poster at China based Web site Weiphone [English translation] posted an image claiming to be the spec sheet of Apple's upcoming 13-inch MacBook Pro. The spec sheet discards rumors that next generation MacBook Pro features retina display.

The purported specifications suggest MacBook Pro with 13.3-inch LED Backlit glossy widescreen display with a resolution of 1,280 X 800 pixels, which clearly could not be labeled as "retina display". The processor is Intel Core i5 clocked at 2.5 GHz with Turbo Boost up to 3.1 GHz and 3MB of L3 Cache. It features 4GB DDR3 SDRAM (1600 MHz), 500GB Hard Drive (5000 rpm), Intel HD Graphics 4000, optical drive and built-in FaceTime camera.

Updated MacBook Pro includes two USB 3.0 ports along with Thunderbolt port, SDXC slot and FireWire 800 port. The size and weight of 2012 MacBook Pro is also revealed in the spec sheet which is identical to the current 13-inch MacBook Pro models. The dimensions of tablet are 12.78 X 8.94 X 0.95 inches and it weighs 4.5 pounds.

The spec sheet seems to be associated with an entry-level MacBook Pro as it lacks some premium features of high-end MacBook Pros like slim design and retina display. Apple is also expected to release 15-inch MacBook Pro which may include retina display and thinner design at the June event. Citing unknown sources, 9to5Mac reported on Monday that Apple will release two 15-inch MacBook Pros featuring thinner design and retina display at WWDC 2012 event.