Now that the MacBook Pro refresh has happened and the iPad 2 is out, what's left for the rumor mill? The iPhone 5 of course. Citing a Chinese source, Japanese site Macotakara claims that Apple is abandoning the current iPhone 4's exposed antenna/glass backside construction for the iPhone 5. The iPhone 5 will supposedly have an all-aluminum rear case similar to the iPad 2. Wireless signals will penetrate the case via the Apple logo, which will be made from a plastic resin, presumably similar to the black bar on top of the 3G iPad 2.
Macotakara has had a fairly good accuracy rate in its rumors so far, although Economic Daily News, Macotakara's source for this rumor, has been less reliable in the past. Macotakara's reports nailed the iPad 2's announcement and shipping dates, and it got some of the hardware details right as far back as December. If the site is getting its information directly from Chinese sources as it claims, that might account for its accuracy rate.
A complete case redesign for the iPhone 5 isn't beyond the realm of possibility, but personally, I'll remain skeptical until there are corroborating reports from at least one other source. The iPhone 5 will likely be announced in either June or July of this year, and in the meantime we can expect to hear a lot more about the forthcoming device -- not all of it accurate.