Are you referring to the DVR (1216 or 1225) or a standard set top box (1200)
Currently both the small capacity 1216 and large capacity 1225 are used, in addition a second large capacity DVR the 2250 was released late 2011. Generally two ways for DVR replacement 1) equipment failure (red X or does not work) 2) request upgrade ($50 charge)
The 1200 set top boxes are stilling being used areas with Cisco boxes he newer black units. Units replace as they fail.
In addition standard set top boxes could be upgraded ($49) to wireless (Max 2) which are also black.
*I am an AT&T employee and the postings on this site are my own and don't necessarily represent AT&T's position, strategies or opinions.
*The views and opinions expressed on this forum are purely my own. Any product claim, statistic, quote, or other representation about a product or service should be verified with the manufacturer, provider, or party.