The pet is automatically associated with your Battle.net account when you register your StarCraft II Collector's Edition CD Key. You cannot give it away.
If someday you do decide to play World of Warcraft, you will have a shiny new mini-Thor waiting for you in your mailbox.
It's awesome, by the way.
For protection warriors, Mastery is actually a great stat.
This thread on elitistjerks.com contains good theorycrafting data for protection warriors; particularly this section:
Survival Stat Priority:
Stamina > Mastery > Parry > Dodge
Stamina is still your best stat, but not to the extent of sacrificing everything else as was the case in WotLK. Conserving healer mana is a very real concern now. Mastery is your best stat for smoothing out incoming physical damage, and also increases rage generation through blocks. Parry provides the same avoidance level as Dodge now, but also procs the Hold the Line talent. Dodge will become more valuable as gear ratings climb higher to reduce diminishing returns losses from over-stacking the other stats.
For specific calculations, WarTotem over at TankSpot has made a lovely spreadsheet containing all the information you should need!
An important point is the "point of unhittableness" (ie when you have a combined chance of 102.4% to dodge, parry or block), at which point a boss can no longer "hit" you, only block dodge or parry. At this point mastery becomes an even better stat than it was before, since 60% damage reduction from a block is better than 30% damage reduction from a block!
You can also read through both threads for detailed discussions of the mechanics involved by people an awful lot smarter and more in-the-know than I am!
Best Answer
It is possible to get Warforged items with the bonus roll.
Although this post is from July 2014, there has been no indication that this has changed.
Unfortunately for me, my bonus rolls in this first week of Highmaul hasn't given me any loot, let alone Warforged! :)