According to a ThinkSecret report, Apple's next iBook may have a 13.3" inch wide display.

The new screen of the iBook will have a WXGA resolution of 1280x720 pixels or about 15% more pixels than the current iBook.

The site claims that the current 12" iBook could remain alive but the 12" Powerbook's days are counted.

In a report we published back in October 2004, anonymous sources had told MacosXrumors that the 12" Powerbook would disappear and would be replaced by a 13.3" laptop with higher resolutions. At that time, it was supposed to be a future Powerbook G4 though.