Minor note, but the p (or i) is not important here, so it would just be HD720 or HD1080. The p/i denotes a method of displaying the image, either through interlacing[0] or progressive scan[1].

[0] http://en.wikipedia.org/wiki/Interlaced_video [1] http://en.wikipedia.org/wiki/Progressive_scan

However, its highest (17k fps) speeds are at much smaller resolutions, and it's more like 1000fps and under at the higher ones, which isn't quite as impressive, although still fast.