"When shooting 30p, the camera operator has the ability to capture 30 full frames per second. When shooting sports, users can freeze an image, capturing the full frame, or slow motion down for that "instant replay" effect."

Can someone who understands comments on the "slow motion down for that "instant replay" effect."

Is this a new feature? How would that work?

I think the deal is because its progressive scan (full frame no fields)
that as you step through the frames you don't get that annoying
comb effect of regular NTSC.

Real sport slo mo is achieved with VERY expensive high speed video
cameras. From what I've been told there are only a few of them in the USA
and they are usually booked for major sports events. Their
cost is/was around $250K.

720P (varicam) is a much better choice for video slo mo than the XL2 IMO.