It's a TV panel that they added DP to. Mixed feelings about it. It's good it has DP, but 40" is a tv, not a computer display.

V I D A L
I agree with Brad.. feels weird. I you are to get a display that big, you better get a 4k TV with 120hz instead.

You've gotta be careful when marketing types say 120hz on a 4k tv. When they say 120hz, they mean internally to the panel via signal processing that they're doing frame interpolation to emulate 120hz. It's not 120hz port input. Only way that would occur is if you had some magic DisplayPort 1.3 UHD TV that doesn't exist yet. Maybe next year or some prototype at CES 2015, but it doesn't truly exist yet other than in a VESA DisplayPort 1.3 spec that just came out.
 
For example the Seiki UHD TV's all claim 120hz, but don't even have a DisplayPort in them let alone HDMI 2.0. They're 30hz HDMI 1.4a ports. It's misdirection via marketing where information is presented out of context.