Rumor has it (on WoWInsider) that Patch 2.4.2 will change Riding Crop and other mount speed trinkets, making them an enchantment to be applied directly to the mount.
What does that mean for leatherworkers? It means that instead of every level 70 toon needing one Riding Crop, they would need two – one to apply to their flying mount and one for their riding mount. And also one each for their warbear, phoenix, nether ray, etc… if they are mount collectors.
If this change makes it to the game, it should bring a short-lived spike in leatherworking business. Many leatherworkers will just spam the Trade channel offering to make them but needing the mats supplied, and relying for tips for profit. Although it might be risky due to the expense of the Primal Might, you might try making a few in advance to put on the AH or sell in Trade. I can grind out the mats for a Primal Might in one afternoon, and a guildie can do the transmute for me.
For those who are skinners but not leatherworkers there may be a run on Heavy Knothide Leather. I’d gather some up in advance, just in case. Also – enchanters may have a spike in demand for Primal Might transmutes. I doubt there will be too much effect on the Small Prismatic Shard and Arcane Dust business because the AH is usually flooded with those (on my server, at least).
I wouldn’t bet the farm on any of this. It may not be part of the final live patch. And even if it is, some players might not think it’s worth it to speed up both of their mounts if they use one much more than the other.