Preview at WWDC likely in June, followed by September launch.
More New Apple Products... This Tuesday? [Updatedx4]
Sources reveal that shipments of new Apple products (not just Time Capsule) are planned for midweek. Historically, such information tends to reliably predict new product releases. But we can't be confident these necessarily represent new MacBook Pros, or another unexpected announcement (such as premature MacBook or iMac updates).
Previous tidbits of information surrounding the new MacBook Pros have indicated that they will incorporate Penryn processors, an LED screen in the 17" model, and the new-and-improved multi-touch trackpad found in the MacBook Air.
Updatex2: Best Buy part numbers reportedly show new model numbers for Mac Book Pros priced the same as current models, according to two posters. Appleinsider confirms new Best Buy part numbers.
Update 3: Page 2: MacBooks, Not MacBook Pros?
Update 4: Page 2: MacBooks AND MacBook Pros?