This is something that is rarely spoken off, but I read from several sources that mounts in Cataclysm will be scalable. This would mean that, for instance, the normal speed land mounts would become epic speed land mounts, once you learn the next riding level at level 40. Likewise, the normal flying mounts would jump to epic flying speed, and then the "extra epic" speed, again, once you learn the required flying skill.
If you ask me, this is great. Some of those normal speed mounts look pretty good and it would reduce the clutter in the mount menu, since you can pretty much click any mount without wings and it's OK. It also increases our options at all levels. What do you guys think?