This is the ZTE Avid 4G, heading to MetroPCS
While no specs were included with the tweet, it would appear that the ZTE Avid 4G will offer a 4 inch display, a front-facing camera and a 3.5mm headphone jack. Based on the rendering, it is a good bet that Android 4.0 is installed. MetroPCS customers have until the middle of the next year before losing their independence. Then, it will all be about getting the pre-paid carrier's customers to migrate to T-Mobile.
source: evleaks via SlashPhone