The rumors about MacBook Air and MacBook Pro have recently been about whether the new MacBook Pro will get a new look that will be more similar to Macbook Air than the present model. But now, Taiwanese DigiTimes is bringing some even more interesting rumors.

Apple reportedly is set to launch its new MacBook Air series notebooks with panel sizes of 11.6-inch, 13.3-inch and 15-inch in the first quarter of 2012 and will directly compete against ultrabooks from PC brand vendors, according to sources from the upstream supply chain.

The sources noted that related upstream players have already started pilot production of the MacBook Air models and will add a 15-inch model into the product line to expand its reach in the ultra-thin notebook market.

If the rumors of a 15-inch model are true remains to be seen, but at least the market is definitely ready for it.