It's unclear "how" high-resolution that display will be, but we're guessing at least 2048 x 1536, or whatever is required for Apple to dub it a retina display. The source said the iPad 3 is scheduled for a March launch, in line with the annual refresh, although it could be "shown off" as early as January, depending on how things go.
Of course, this conflicts with earlier reports that the March release of an iPad would be an upgraded iPad 2, with the iPad 3 coming later in the year.
The source added that the MacBook Pro will finally get its redesign. Expect a new, thinner MacBook Pro to show up in 2012.
A summer 2012 release would seem a little early for a new iPhone, though admittedly the iPhone 4S was "late." It's also hard to imagine Apple scrapping the teardrop design, which we heard was very close to production, but just not ready in time for the mid-October launch of the new iPhone.