Ron Barry said:
My guess is that USB Extra storage comment means in terms of Archival. Being able to roll off content off the main drive based on how the USB archive support has been described in the past. I doubt it is in terms of additional storage that can be used for upto recording three while watching two back.
BUT, it could be done so that this is transparent to the user. In the background while the DVR is "off", it could copy the movies to the USB drive and flag the data on the DVR itself as "Available to delete" if neccessary and show the space remaining as if it's already been deleted.
If you want to watch a recording that's still actually on the DVR then it plays directly just as it is now. If you want to watch a recording that was nuked to make room, then it starts playing over the USB stream.
Theoretically you might need to be able to supply 2 streams of read data from the USB in this instance, but the odds of both tuners needing access to archived-only data simultaneously is very very low and they might simply make a note on the feature that it can only support 1 HD (MPEG2)+ 1 SD stream at a time, 2 MPEG4 HD streams, or 2 SD streams, or somthing similar. (does USB 2.0 have the bandwidth for two MPEG2 streams?)
If you have any restrictions like that, dish might also introduce extra types of "protect" for the recordings... like "Local only" to prevent it from being moved.