Anything discovered and mentioned should be taken with a grain of salt for now. Things could drastically change at any moment, so it's probably best not to take any of it as absolute fact right now. Since we are merely the audience and we don't have an in depth view of what's behind the scenes, all discussions are really just speculation.
Now that that disclaimer is out of the way, let's talk about the current situation on beta servers where both the Pet Journal and spellbook companion tab exist as two independent collections. There's still no telling if the spellbook companion tab will remain in-game once MoP is released, but as it is now, well, there are pros and cons to having two collections on one character.
Am I for having both available to my druid? Or would having just the Pet Journal be enough? To answer that, let's take a look at those pros and cons.
Pros for maintaining both the Pet Journal and Spellbook Companion Tab as independent collections on a single character:
- You could use the Pet Journal to trade away a pet, but still be able to summon that pet through the spellbook. In this situation, you would only lose the ability to battle with said pet and the renaming ability (just for that pet). (Note: I'm not even sure if this an intended feature of pet trading or if it's simply a side effect of two independent collections existing on the beta.)
- Pet collecting achievements could still be individual for each character, as it would use the spellbook companion tab to track how many pet spells that particular toon knows. (On the other hand, if achievements are going "account wide" as Blizzard has mentioned they would look into trying out, perhaps this doesn't matter anymore.)
- Players can maintain their sense of individualism on a character while still having the perks of accessing the Pet Journal for pet battling.
- It allows collectors to recognize and designate a "main collector" character. The Pet Journal simply lumps all pets found on an account into one area accessible by all toons, but the spellbook tab would retain the original collection information.
Cons for maintaining both the Pet Journal and Spellbook Companion Tab as independent collections on a single character:
- It complicates how pet trading is handled, since to replace a removed pet back into the Pet Journal requires a character that doesn't already know that specific pet's summoning spell. Otherwise you get an "Already known" error.So far it's looking as though keeping both the Pet Journal and the spellbook companion tab in the game would probably not be the best idea. It would make pet trading and renaming more complicated than it needs to be.
- Some may view trading a pet away yet being able to summon it through the spellbook as "cheating" the system. It would also give those with extremely rare pets an advantage over others. They could monopolize the market with these pets and without penalty since they wouldn't lose the ability to use the pet themselves.
- Having two sets of collections might negatively impact other areas of pet collecting yet foreseen. Not to mention it's probably a bit of a coding headache to make sure both are working properly and not causing the other to bug out or interact improperly.
- New players might be too easily confused with two independent collections.
Another option besides keeping both or tossing one or the other is combining the two collections. It could work out but only if actions taken in the Pet Journal directly affected the spellbook companion tab. Renaming, trading, etc. through the Pet Journal would have to also be reflected in the spellbook. In that type of situation it would mean selling a companion would remove it from the spellbook as well as the journal.
Then again, a new question/problem arises: should actions affect just one specific toon's spellbook companion tab? Or the spellbook across ALL characters?
Right now each character's spellbook tab is unique to that toon. I may have the X pet learned on my druid but not on my hunter. So if I happen to have Y pet on both toons, but sell it on my druid, should it also disappear from my hunter's spellbook?
Combining the two has the potential to be not only a player headache, as we would have to sort out and remember which character has what pet and so on, but it would probably be a coding nightmare. I can also imagine all sorts of bugs popping up because of it. It just seems to complicate things more than necessary.
I really don't see Blizzard releasing it as it is on the beta. In the end, I think we're going to lose one or the other, and since Pet Battles is directly tied with the Pet Journal and Blizzard doesn't look like they plan on giving up the battles feature any time soon, we're most likely going to lose the spellbook companion tab.
How this impacts pet trading and the collecting of wild/new pets, we'll have to wait and see. It might make things simpler, but will it be for the better or for the worse?
At the moment, I would be ok with having just the Pet Journal at my disposal in MoP. It provides so much more utility than the current spellbook companion tab. The main thing that I would miss would be the ability to summon a pet despite having traded/giving it away. But it's not even known if that's an intended feature of pet trading, so perhaps I wouldn't even have the opportunity to miss it.
If I were heavily into RP, I think I would miss in the spellbook companion tab a bit more, though. The pets found in there is exclusive to a particular character, and losing that would mean possibly losing the feeling of "being" an individual toon.
Now that I think about it, losing the spellbook companion tab would mean less of a distinction between my characters and blur the lines of which is my main collector. I guess it's something I could adjust to overtime. I wouldn't be "losing" my main collector in any sense, but only I would really be able to tell that my druid is my "main collector". Other players wouldn't be able to easily and quickly identify my main collecting toon by just looking at my characters' armory pages. (At least that's what I'm guessing since the armory seems to reflect the data that's found in the spellbook companion tab. I'm not sure how the armory will present information that's account wide in MoP, or if it will still show individual toon stats.)
Well, it's still too early to say what will happen for sure. Maybe developers have found an ingenious resolution that doesn't overly complicate things, is easy to maintain/grasp, and would appease the majority. Keeping both, removing one, or combining the two are only three possibilities.