A very early instance of a 2011 iPhone case has shown up in a listing at Asian trading site AliBaba. Guangdong-based Kulcase is selling what it claims is a crystal case for an "iPhone 5G." The construction and the placeholder inside it suggest not only a larger, edge-to-edge screen but that the flash has moved from directly next to the rear camera to the corner on the other side, presumably to improve its performance.
Whether or not the case is accurate is difficult to determine. Some rumors have pointed to a radical overhaul of the iPhone for this year that would support the existence of an edge-to-edge screen and possibly other changes. Others have pointed to just a modest iPhone 4 respin, although at least one of these has referenced an edge-to-edge display.
A side glance isn't available and would help determine the plans, since the argument for a major redesign has pointed to a tapered shape.
Small Chinese companies have, in the past, regularly and illegally obtained Apple design blueprints in advance and started manufacturing cases even when it turned out the design changed slightly before launch. The problem was finally acknowledged this year when Foxconn had employees arrested for passing on iPad 2 information months in advance. A company from Guangdong in the mainland would be an unusual choice given its distance from Foxconn's usual factories, although the cases themselves would ship out of the port of Shenzhen, Foxconn's core manufacturing base.
The new iPhone, regardless of design, isn't anticipated until September but would start manufacturing in July and might give time for early schematics to show.