Apparently, I was thinking of another plasma line and/or brand.
There was one brand/line, recently, where the number after the colon was, indeed, the number of power cycles, which was surprising to me. Before the colon was the number of the hours with a decimel point somewhere in the number, but I wasn't sure of the decimel placement.
Heck, the person writing it could have been wrong, but, IIRC, they were reliable. I'm thinking, now, that it was probably from a Samsung thread
So, yeah, what is the correct way to read those numbers?