Profession Bags Give Bonuses in The War Within - Increased Reagent Gain, Improved Cooldowns, and More

wowhead.com:

Profession bags will be in high demand in The War Within — each new bag comes with a special effect, such as increasing reagent gain or decreasing cooldowns!

Tailors will have a new bag full of tricks once they learn these new recipes, and every profession will want to obtain one of these new bags. Each is Unique-Equipped, so unfortunately you can't double up on effects, but you can equip two different profession bags at the same time — you won't have to choose which of your professions you find more important!

• Alchemy Bag Alchemy BagConcoctor's Clutch Concoctor's Clutch Concoctor's Clutch
  Taut threads perfectly protect it's inhabitants from experiments gone wrong.
• Blacksmithing Bag Blacksmithing BagIgnition Satchel Ignition Satchel Ignition Satchel
  Imbued with Everburning Ignition, sets a Blacksmith's heart ablaze.
• Engineering Bag Engineering BProdigy's Scrapbag Prodigy's Scrapbag Prodigy's Scrapbag
  A container of effortless genius.
• Inscription Bag Inscription BagDarkmoon Duffle Darkmoon Duffle Darkmoon Duffle
  A compartment of mysteries and intrigue.
• Mining Bag Mining BagExcavator's Haversack Excavator's Haversack Excavator's Haversack
  Dusty, but durable.
• Jewelcrafting Bag Jewelcrafting Bager's Purse Jeweler's Purse Jeweler's Purse
  Malleable threads make just enough space for rough edges.
• Tailoring Bag Tailoring BagThe Severed Satchel The Severed Satchel
  A container spun from The Weaver's master artisans, capable of maximizing the value of cloth as elusive as Dawnweave and Duskweave.

Several other bags have been discovered as well, but as of now either have not been renamed or do not have effects attached. It's highly likely we'll see these gain fun abilities and names in a future build!

• Enchanting Bag
• Herbalism Bag — The cooldown of Overload Empowered Herb is reduced by an additional 1% when gathering herbs.
• Hideshaper's Workbag — Does something cool for leatherworkers!