can i hook 2 extenders to a media pc with 2 tuners in it & 2 (or more) people watch live tv idependently?

Answer 1

Yes. Microsoft claims you can hook up to 4 extenders to each PC.

"Windows Media Center supports as many as two NTSC Standard tuners and two ATSC HD TV tuners, for a maximum of four TV tuners in a Windows Media Center PC."

With the new Extenders for Windows Media Center, you can stream the digital media you have on your Windows Media Center PC in as many as five rooms in your house1