Apparently April showers bring May ... MacBook Air rumors.

A rather thin report from Taiwanese newspaper DigiTimes repurposes what a Concord Security analyst said in April: Apple is launching new MacBook Airs this June or July, equipped with high-speed Thunderbolt transfer technology and Intel's new Sandy Bridge processors.

DigiTimes simply cites "makers in the supply chain," who typically know specs about new Apple products even before most of the company. Apple is notoriously tight-lipped about unlaunched products.

As PCMag's lead laptop analyst Cisco Cheng noted in April, the technology inside the existing MacBook Airs, which arrived last October, is incredibly outdated compared to its MacBook Pro brethren.

Current MacBook Air 13.3-inch and 11.6-inch models are equipped with three-year-old Intel Core 2 Duo processors and USB. In April, Apple quietly began replacing the solid state drives (SSD) in the smaller MacBook Air models with faster ones.

Meanwhile, current MacBook Pros, which launched in February, feature Sandy Bridge Intel Core i5 processor (four to five times faster than the Core 2 Duo L9400 found in current, larger MacBook Airs, according to PCMag lab tests), and Thunderbolt transfer technology that's roughly 21 times the speed of normal USB.

Despite all this, the MacBook Air is one of Apple's most popular Mac products. Another Concord Securities analyst recently estimated that Apple shipped 1.1 million MacBook Airs in the last three months of 2010, making it Apple's most successful Mac product launch to date, the analyst qualified.