Given that he mentioned PIP in the next breath, I doubt he's thinking of the existing Plus equipment. I don't know if the HR24 has the capacity to do PIP, but I do know that the HR21-23 do not (they lack rendering facilities for a secondary video stream).
The absence of mention of the client-server model and TiVo (while contemplating adding "suggestions") may also be noteworthy.
Being that the HR24 is a much better performing box than the other HR2x boxes, it may have the horsepower necessary to do PIP. But this could also be an indication of a totally brand new box (not the Tivo one either).
It would be time for one. The HR2x line of boxes is about 4 years old.