Digitimes one of the websites that started the rumor that iPhone 5 will have bigger 4.2-inch screen now claims the screen size won’t change by much. Yenting Chen posted:

Sources from upstream panel suppliers have recently revealed that the iPhone 5’s panel size will still be less than 4-inch. In addition, iPhone 5’s design will be changed to a metal chassis instead of reinforced glass.

The rumored specifications of iPhone 5 include a 4- to 4.2-inch HD touch panel, 8-megapixel camera, Full HD video recording, A5 dual-core processor and new ultra-thin industrial design; however, the sources believe that the leaked specifications are rather the market's expectations for iPhone 5. The sources pointed out that the upcoming iPhone will not have many differences compared to iPhone 4 in terms of components and the panel will still be less than 4-inch.

The sources added that the iPhone 5 will adopt a 3.5- to 3.7-inch panel with a design to allow the bezel of the panel to become thinner and make the screen look larger.

Frankly we don’t know anything about iPhone 5’s screen size, but from what we have heard from our sources Apple had to delay introduction of iPhone 5 because of the new design. Like always Apple was aiming for a June / July iPhone 5 launch, but their partners weren’t able to meet Apple’s standards and quantity requirements for some of the components required by the new iPhone design.

So we seriously doubt Digitimes’ claim “upcoming iPhone will not have many differences compared to iPhone 4”. We don’t think Apple was stuck so long designing the metal back for iPhone 5.