I purchased the SlingboxProHD in September 2009 to watch football while on the road. Hooked it up to my Scientific Atlanta HD-DVR box from Comcast and freed myself from the TV. We primarily use the box in three ways:
1) Away from home via computer to an HDMI-out to hotel TV. 2) On the dual display LCD monitor in the kitchen for a TV where there is no coaxial output. 3) On mobile devices (iPad and iPod Touch) for on the go.
My siblings are also able to share the box and follow hometown football from their homes. Just program the DVR and everyone gets to replay when they need.
Hook up is fairly simple.
Analog Pass-Thru = coaxial from wall to Slingbox to cable box to TV. Digital Pass-Thru = component cables from cable box to Slingbox to TV
There is one caveat though. If your cable box is like most you cannot hook up the cable box to your TV via HDMI. If you try your component outputs will be disabled at the cable box and Slingbox will get no signal. This is a flaw in the HDCP copy-protection scheme which keeps consumers from recording HDMI/High Def feeds (thank you bloodsucking Hollywood!!!!).