What part of "there are other CDMA carriers around the world" did you not understand? GSM may be ubiquitous, but it's NOT a "world standard." It IS a European standard and is used throughout the world, but there is no one-world government saying GSM is the standard for wireless communication.
GSM isn't a world standard? What world do you live in? Sure it is. NOBODY has to announce that something is the "standard" for it to actually be the standard.
Everyone I know drives a car that has round wheels and rubber tires. I believe it's safe to say that the standard is round wheels and rubber tires for the entire world.
However, nobody has announced that I know of that round wheels and rubber tires are the standard for ALL automobiles. People can still produce metal square wheels if they want, but the standard as we know it.... is rubber.
GSM has a world market of 82% while CDMA has only about 18% of the world market. Those numbers don't lie.
So, was there any part of that... that you didn't understand?
EDIT:
See also this article where it CLEARLY tells you that CDMA is the dominant standard currently in the United States, but that GSM is CLEARLY the world standard over-all.
You lose.
http://www.diffen.com/difference/CDMA_vs_GSM