All kinds of strange is surrounding this rumor, so we'll try our best to thumb through the mounds of information on the internet.
TopTongueBarry, a PreCentral forums user and an AT&T IT employee, claims that while the nation's second largest wireless carrier has completed testing for the Palm Pre Plus and Palm Pixi Plus, a third device codenamed "Elan" is slated for testing in the coming weeks. As you can see in the picture above, several accessory manufacturers had listed things compatible with "Elan," but after the codename was unearthed, quickly removed the name from their respective pages. Some are speculating that this device is nothing more than a GSM version of the Pre Plus or Pixi Plus, while others are thinking that this could be an entirely new device in the Palm lineup. A tablet, perhaps?
So, who knows? It could be the rumored C40 that was rumored for Sprint, or it could be the US GSM version of the Palm Pre Plus or Pixi Plus. Personally, I'd love to see the mockup shown in Palm's forums hit retail shelves. Either way, we'll be digging for more information, and will post as soon as we know anything.