“Our sense is that the Mac business is recession proof,” he writes in a report to clients issued Thursday morning. Based on his supply chain checks, Wu sees good news throughout Apple’s (AAPL) product line:

• Rather than the 38 percent year-to-year growth in Macintosh unit sales he had earlier predicted, he now thinks growth may be closer to 42 percent.
• After a strong start and then a lull, he sees Macbook Air sales picking up rapidly. “Customers are attracted to its super thin form factor and do not seem to mind some of its limitations.”
• He’s seeing a bump in iPod sales following the shuffle price cut, and now expects iPods to come in at the high end of his 9.5-10 million unit range (but lower than the Street’s 10.8 consensus).
• He sees a pause in iPhone sales following the well-regarded SDK announcement as customers wait for the June release of iPhone 2.0. He’s modeling 11 million iPhones for the year, slightly ahead of Apple’s 10 million target.
• Falling prices in component parts should sweeten Apple’s March report, due out April 23, and Wu is raising his estimates accordingly. He writes: “For the March quarter, we are now modeling $7 billion and $1.10 in EPS (from $6.9 billion and $1.02) vs. consensus of $6.92 billion and $1.05 and its guidance of $6.8 billion and $0.94.”