Shaw Wu of American Technology Research was an early skeptic of efforts to unlock iPhones to run in other countries and on networks other than AT&Ts. Last October, when some analysts were putting the number of hacked iPhones as high as 100,000, he insisted that the real number was so small as to be “immaterial.”

Today he’s saying something quite different. In a report issued to subscribers, he’s come out with the highest estimate of unlocked iPhones we’ve seen to date. He writes:

We believe the hacked iPhone market is much larger than expected. Our sources indicate that iPhone is being used in 35-40 countries vs. the 4 authorized countries. Out of the 4 million iPhones shipped, we estimate at least 1 million, and perhaps as high as 1.5 million may be hacked.

Although Wu concludes that Apple’s fundamentals are strong and that the company is better positioned than most to weather a looming recession and a slow-down in consumer spending, the rest of his report makes for sobering reading.

• MacBook Air sales look “somewhat underwhelming,” although the new machine is helping drive traffic to the Apple Stores, where other Macs are showing “continued momentum.”
• iPods appear to be tracking 9.5 to 10 million units for the quarter, below the most bullish estimates of 11-12 million units. “We do not think the overly optimistic have factored enough of a seasonal decline and overestimated low-end shuffle demand,” he writes.
• iPhone shipments “appear weak” and AT&T subscriptions are “looking light,” with the above caveat about how many iPhones are being hacked.

In the end, Wu believes that the number of unlocked iPhones won’t matter as much to Apple as it might to AT&T. “While hacked iPhones have some impact to deferred revenue,” he writes, “we are not overly concerned as iPhone is only a 3% contributor to reported revenue. Even if we model zero iPhones for the March quarter, it would only have a $0.03 impact to EPS.

For more on where those unlocked iPhones are going, see The iPhones of Equatorial Guinea.