While the Electronics Entertainment Expo rolls on, Apple is shifting into high gear as it prepares for the Worldwide Developers Conference (WWDC).

Apple’s big show runs all next week, and the tech community is abuzz with speculation about what may come out of the conference. Some things that are definitely expected: more details about Mountain Lion and iOS 6, for example.

But most of the excitement heading into the conference revolves around the hope that Apple will be showing off new hardware this year to its developers, rather than making the operating systems the main focus of the summer.

Fresh speculation over what’s in store for the 13-inch MacBook Pro bloomed Tuesday after a forum poster on a Chinese Web site put up what is supposedly the spec sheet for the new laptop. As CNET reported, the picture claims the laptop has a 2.5GHz dual-core Intel Core i5 processor, an upgrade from the 2.4 GHz chip in the cheapest 13-inch model. The image also shows UBS 3.0 ports, a possible Ivy Bridge processor and Bluetooth 4.0 support. It doesn’t however, make mention of a retina display.

Apple did not immediately respond to a request for comment on the supposedly “leaked” specs.

Grainy photos on Web forums aside, over at 9 to 5 Mac, reporter Marc Gurman’s sources told him that Apple is planning to update at least four out of its five Mac lines — the MacBook Pro, the MacBook Air, the iMac and either the Mac mini or the Mac Pro.

Gurman reports that the company will release reconfigured versions of the 15-inch Mac Book Pro with a thinner profile and a retina display, while giving a similar treatment to the 11-inch and 13-inch MacBook Air. In the desktop world, Gurman’s sources say that the iMac could also see a makeover that include a higher-resolution display, but said it’s not clear if that refresh will be part of next week’s announcements.

The MacBook Pro refresh has been the most persistent rumor as we head in to WWDC, with reports from Bloomberg also claiming to tip Apple’s hand regarding a refresh that includes thinner laptops that run on Intel chips.

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