One of the biggest problems I had leveling my alts this expansion was that with the speed of leveling, I often outleveled my professions. This meant that, before the catch up mechanisms for herbalism and mining were implemented, I had to go back to content as far down as classic WoW zones to get my shaman caught up on his herbalism. That got fixed when a change was implemented allowing us to use Mists of Pandaria plants and mining nodes to level up our gathering professions. Now Blizzard profession designer Hwoome has good news.
@Thoorium Of the various catch up systems we experimented with in Mists, we liked herbalism/mining the best. Plan is for more like that.- Hwoo (@hwoome) March 20, 2014
But what about crafting professions? Well, we don't know yet, but the plan is apparently to tie in with the gated material generation. This is in my opinion welcome news - especially for people boosting to 90, you'll be able to level your professions in the new content. That's a huge plus.