I figured I would chime in with my 2 cents.
As a hunter that has played and experienced each of the specs through all the many changes that Hunters have seen over the years I have to say a couple of things.
The ONLY thing that makes BM fun
for me is the fact that I get to run around with King Krush by my side, the two of us taking down bosses, Alliance in PvP ect. It isn't the minor attacks speed increase, the 3-second stun that my pet gets, or the big red button.
First, strictly speaking,
in my opinion BM has little utility in comparison to the other specs,
Intimidation: the 3-second stun is on a 45 second cooldown (with talents of course, 1 min cooldown otherwise) while nice is no where near as useful as scatter shot (which I personally love)
The Beast Within: a 10 second minor increase to damage for you and your pet (10% for you 50% for your pet) and immunity to CC for its duration is nice, and is essentially a second PvP Trinket is on a 1 min 20 sec cooldown (talented and glyphed of course, 2 min cooldown otherwise)
The synergy that this ability gives, the TWO of you get big red and deadly for 10 seconds to take down a target makes the BM spec kind of fun. While it is used primarily as a burst button, this ability doesn't hold a candle to the burst that both Survival and Marksman can throw down (Chimera Shot, Explosive Shot), nowhere even close.
The only thing that makes it shine for me is the CC immunity in PvP, aside from that it is about the same as using a DPS trinket or getting a proc from my armor or trinket.
If I could have King Krush and spec Survival with its wyvern sting, scatter shot, and not to mention explosive shot, or if I could spec Marksman with its double trapping capability, silencing shot, chimera shot, and bleeds on (some) shot crits too, it would be no contest.
Second, I enjoy the variety of different play styles, but the most boring of them
to me is BM, there is little variation (steady shot, arcane shot, aimed/multi shot, ...rinse repeat), though sometimes that is good, (like when I am grabbing a drink and not seeing my DPS go down) it is very difficult at times to enjoy, while Survival and especially Marksman specs are much more dynamic, having to change your play style to match your opponent and situation. If I had to choose which play style I would want to play, it would again, be no contest.
I understand why hunters would like to have these beautiful pets with them when they are raiding ICC, since BM isn't raid viable in any kind of guild that is focused on raiding. (I have raided ICC as BM, the last one I was in I got allot of dirty looks even though I was pulling better DPS than all but one of the MM hunters in the raid, which I shouldn't have been able to do, but I digress.)
But you must understand the resistance that BM hunters, (and yes, I am dividing the Hunter community into factions, because they are divided on this issue) would have to this change. To a MM or SV hunter, it doesn't seem to be that much of issue ("its just a cool skin" ...ect, which is true) but we BM hunters are quite attached to our pets and don't want to let just anyone have them. Maybe it is a bit selfish, but considering it is THE last talent, taking 50 others in BM to get to, I think we have a right to be.
Simply giving us two pets instead of one, or giving us some "insert name here" shot would take away the shine, the uniqueness that Beast Master Hunters have right now.
While I am resistant to the idea, I love discussing it, and am always open to hearing a differing opinion.
Who knows? Maybe I can be convinced
(edited to add this)
Now, I don't agree that BM should be this way, BM should have more than just a shiny pet to make it unique, to make it stand out and offer something unique in comparison to the other specs. Maybe pets that are REALLY tougher, i.e. Tenacity Pets actually having Tank like Hit Points (30-40k at 80), ect.
Of course what these changes would be I am not sure, but I am willing to muse over them.