The fastest 13-inch MacBook Pro and an entry-level 15-inch model are proving to be particularly popular with Mac shoppers, argues Piper Jaffray analyst Gene Munster. Shipping delays at the Apple online store are currently between seven to 10 days for the pair, which is said to be unusually significant in that 13-inch MacBooks have not seen similar delays for over two years. At the time, delays were also just five to seven days.

Munster adds that during a brief survey of 10 retail Apple Stores, he learned that seven were missing at least one 13-inch Pro line, sometimes the slowest variant. "We see this as a sign that demand is outpacing the company's build expectations, and it may take several weeks to reach a supply demand equilibrium," says a memo from the analyst. Apple recently began its annual back-to-school promotion, offering a free iPod touch with every Mac.

The company is meanwhile believed to be tracking unexpectedly high iPhone 3GS sales, as reflected in figures of over 1 million units during the launch weekend. The device launched in just eight countries, and may still have beaten iPhone 3G performance, which had the advantage of 21 initial regions. Munster also cites a leaked AT&T memo, which could hint that Apple has concealed the true success of the 3GS.

Some five million iPhones are expected to have shipped in the June quarter, "significantly above" consensus estimates. Mac shipments are forecast to be 2.2 million, down from 2.5 million in the same quarter of 2008.