Thanks to Nayuki who works on MLP and can be found over on the Allspark forums, we now know the reason why the official MLP guidebook names Cloudchaser as Stormwalker! According to Nayuki, both are technically right due to some interesting circumstances:
"I know you guys have moved past Hurricane Fluttershy already, but there is something being discussed on other fansites that I'd like to clear up.
"The Elements of Harmony" an official MLP guidebook is coming out soon and people have been discussing a naming issue that has appeared in a photo of one of the pages:
(IMG:https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgneOlkTb-dKmIpa_I8vPyq5N9ayq1dt7NFhq3DFnla7TwAySHKSxPcywBPBH6gP_YZOwU4vj6PVQwKnCiCUGeRA4t_gFnMnNYPBzF3-hYu4dJt9pElD8WyJXKocLvua3YayIJpw-5X_3g/s1600/1.JPG)
As you can see here, Cloudchaser is listed as being named Stormwalker. Many people are assuming the book is in error, which isn't really the case. I was one of the artists directly involved in the mix up, so I figure I can clear it up a bit.
The name for the pegasus in our files at the studio is in fact Stormwalker, so how did she become Cloudchaser in the show? Well, in the script for Hurricane Fluttershy, there was both a Cloudchaser and Stormwalker. Stormwalker was cut before storyboards, and Cloudchaser was never designed. The storyboard artists used the Stormwalker design in the scenes where Cloudchaser was in the script and I posed them out in layout.
So yeah, the show and book are both right. Weird."
Interesting, eh? You can find the source for this information here.
