For those wanting a quick and easy comparison between sRGB and Rec. 2020/Rec. 2100, here's the colour space mapped out on a CIE 1931 xy chromaticity diagram.
The summary is that screens supporting Rec. 2020 or Rec. 2100 offers a wider gamut than sRGB (40% wider).
Those deciding on the direction of the future of displays, especially the trend towards "HDR" technology, should look into Rec. 2100.