Steam to add ‘big picture’ mode

Valve have announced plans for a new “big picture” mode for its Steam digital distibution platform. The mode will concentrate on “controller support and navigation designed for television interaction”.
“Our partners and customers have asked us to make Steam available in more places. With the introduction of Steam on the Mac, and soon in Portal 2 on the PS3, we’ve done just that,” said Doug Lombardi, VP of marketing for Valve.
“With big picture mode, gaming opportunities for Steam partners and customers become possible via PCs and Macs on any TV or computer display in the house.” 
Just what form big picture mode will take is unclear. Will it simply be an optional layout design? A new piece of tech that streams Steam from your PC to your TV? 
With the majority of modern PCs shipping an HDMI output, a simply interface upgrade seems like a fairly moot point and certainly not something to make to such a fuss about.
Anyway, controller navigation support will be nice. More details are expected from the Valve camp during this week’s GDC.