We've already heard reports that both Apple and Samsung will unleash tablets with high-DPI displays next year. According to a story posted by DigiTimes this morning, the high-DPI fever will affect Apple's MacBook Pro notebooks, as well.
The site foretells a "new MacBook Pro lineup" with 2880x1800 displays, which "sources in the upstream supply chain" expect to see in the second quarter of next year. That resolution, of course, would offer exactly four times as many pixels as 1440x900, the display resolution of Apple's current 13" MacBook Air. (The 13" MacBook Pro is still stuck with a 1280x800 display.) Quadrupling the number of pixels is exactly what Apple did with the iPhone 4's "Retina" display; it allowed non-high-DPI images and websites to be resized cleanly, improving compatibility with legacy content.
DigiTimes goes on to note that Acer and Asus are cooking up ultrabooks with 1080p panels, but I'm not sure that's quite in the same league. Sure, an 11.6" laptop with a 1080p display would be nice, but keeping user-interface widgets the same size as with a 1366x768 could involve some messy resizing and interpolation. (1920x1080 divided by 1/4 works out to 960x540, which doesn't correspond to a common PC laptop resolution today.) Of course, there's a chance the 1080p panels will only show up on 14" and 15" ultrabooks, in which case there would be nothing all that groundbreaking about them.