In patch 3.0.2, several special attributes were added to gathering skills to make them even more desirable, aside from being great ways to farm gold. Herbalism has received the Lifeblood Over Time healing ability which allows Herbalists to cast a very small heal over time for themselves. Skinning received the Master of Anatomy passive trait which grants skinners an increased critical strike rating. And finally, the mining gathering skill has been given the Endurance passive trait which provides miners with more stamina.
The Stamina attribute is a passive skill and scales with your mining skill level. For example, at level 75 mining, you will receive your first rank of resistance which will provide you with 3 more stamina, which equals a health increase of 30. At the highest level (a mining skill level of 450 or a rank 6), you will receive 60 more stamina, which equals 600 additional health points.
The addition of toughness, life force, and master of anatomy adds an additional factor to consider when deciding which professions to choose. Any tank that is looking to complete as many health points as possible will definitely want to engage in mining in order to gain the Toughness attribute. DPS classes might want to consider looking at the Master of Anatomy passive trait, and anyone interested in a little healing might want to consider Lifeblood (although I find this one the least useful of the three). All in all, toughness is just another reason to get into mining, even if you find yourself a priest why pass up 600 more health and a great rallying profession, unless you don’t already have your two profession slots full.