It’s a globalization thing. They want to get all of the currency the same, so they’re working with general concepts - change the size, add color, change the placement and shapes of the illustrations, etc.
Then one day, magically, why, all the currencies are SO close to each other, why don’t we just have one, hmmm? I mean, after all, they almost look the same anyway, so why not? And a poll was taken from Women’s Daily that shows how convenient all the different colors are. And they’re prettier, too, and more appealing to women, finally, after hundreds of years of having to deal with ugly green male-dominated money design.
Oh and look - there’s an iPod App for the new money, too!