My take: A responsible raid leader is primarily concerned with which tank will get the raid through an encounter, and only distantly concerned with any loot fights that will erupt afterwards, so I think this has minimal direct impact on bear representation. It is a potential source of resentment among melee DPS and hunters, and it's certainly not going to help your raid in the early weeks of hard-mode attempts with a limited number of drops to go around. However, it's a problem that eventually solves itself after a few months of farm content.
To the extent that opportunity cost plays a role in bear representation, I would guess its impact is felt most in competitive raiding guilds while realm-firsts are still up for grabs. If you're in any situation other than that and your raid leader is making tank choices based on something like this, your raid's got more serious problems than who's tanking what.
Complaint #4: Early Wrath weaknesses in 5-mans left a bad impression on players, and this bled through to raid content.
"Who's your least favorite tank to heal and why?"
"My least favorite in a 5 man is a druid. It's not their fault and I still love them to pieces but they have the biggest challenge for maintaining aggro on groups. In a Pug situation, I will outright decline if the tank is a druid."
We've talked about this previously, but as a TL:DR, bears probably had the most difficulty of all four tanks with dungeons and heroics in the first months after Wrath went live. This was due to an unfortunate combination of factors -- namely, relatively weak AoE threat generation coupled with buffs to DPS' AoE capabilities, and the early lack of a block mechanic coupled with healers starting heroics in greens and blues. Players noticed, with bears being the commonly-cited "least favorite tank" in early content.
My take: A lot of the problems described in that article have since been dealt with, or minimized as healing efficiency outscaled tank HP. What (if any) longterm effect they had on bear population, I don't know. Short of access to statistics on exactly when the bear decline really started, this is a fairly murky issue, but one of the things you'll notice from the linked thread is that a lot of healers were talking about bear tanks disappearing as early as December 2008. More on this as we get to #8.
Otherwise, I'm reduced to quoting myself: we're not a bad tank, we're just the tank whose particular weaknesses are least suited to how players expect to complete modern heroics. This has less to do with the Feral spec (or any tanking spec, really) than it does with the attitude change on the part of the player base between Burning Crusade and Wrath. DPS players have become accustomed to shifting the larger share of responsibility for threat management to tanks, and they don't expect to be constrained by a kill order, the need to CC, or conservative use of AoE (anyone who doesn't believe me on this count hasn't pugged a 5-man since patch 3.0.2). This is an intimidating barrier to entry for new tanks, and particularly for new bears, as the bear's weaknesses in 5-mans (the lack of burst AoE threat outside of a cooldown and no ranged silence) are going to be magnified by tanking for DPS who outgear them.
Complaint #5: Bear gameplay is boring. Too much of the bear's effectiveness is baked into talents rather than being determined by player skill.
"I wore the letter off my Swipe hotkey."
Anyone who's played both a protection warrior and a druid tank can tell you that the bear plays like the CliffsNotes version of a warrior, with ability differences typically being worse for the bear. Discrepancies are generally compensated by feral talents, and while that's necessary to make the bear a viable tank despite its restriction to DPS leather, not many of them add options to what's already a limited tool kit. The single-target tanking rotation isn't terribly different from other tanks', but in AoE situations and 5-mans, things devolve into swipeswipeswipeswipeswipeswipeswipeswipe pretty quickly.
My take: Bears being "boring" to play is by now a common charge on the Tanking forums, but it's a charge that's often leveled by people who don't actually play them. I'm not bored playing my bear tank and I'm especially not bored playing the druid class as a whole, but is has to be said that the original vision for the bear -- namely, to be a weaker copy of the warrior -- is still dogging the spec. Almost everything in the bear's toolkit has a direct counterpart in the warrior skill set, but the skills that most distinguish us from other tanks (Rebirth, Tranquility, Innervate, and improved DPS from cat form once your tank target has died) are inaccessible as long as the druid's still getting hit by a mob. It might be fair to say that the druid is the best possible tank to have when you don't actually need them to tank, and this is both a disheartening "niche" and a strong incentive not to use them in a main tank capacity.
We're not the only tank with that problem, and maybe it's no accident that Blizzard's singled out both bear and paladin tank population for comment. Paladins have complained for years that they're relegated to AoE and add-tanking for similar reasons. They're so good at it (and rage tanks were once so poor) that you had to be crazy to put a paladin on, say, Morogrim Tidewalker instead of putting them on the adds. But paladins have at least one thing going for them that we don't -- they don't lose 3/4 of their skill set shifting into a form that allows them to tank.
Complaint #6: Gear consolidation often results in druids looking insanely stupid in caster form.
Allie: (In Ulduar), all of the non-set melee leather was oriented toward rogue tier, which had the effect of making druid (tanks) look like a postmodern clown on the run from Cirque du Soleil.
Matt Rossi: Druids look like they got into the craft bin at the local thrift shop.
Almost all non-set melee leather drops are designed to complement rogue tier, and, well, let's face it; rogue and druid pieces aren't usually a good match for each other. If you've ever seen a tauren rocking a mixture of Nightsong with non-set pieces, a Garona's Guise, and a Lotrafen, then you've already seen this problem. When Blizzard releases new tier sets, an experienced feral knows enough by now to bypass the druid set, pop the cap on the nearest gin bottle, and head for the rogue set -- because that's mostly what you're going to look like.
My take: When the inability to see your gear while tanking can be considered a feature rather than a bug -- that's bad. Tier 9 has escaped the worst of it (sort of) with all druid and rogue gear being recolored versions of the same skins/models, but I think we can all agree that Tier 8 was its own special brand of hell. As things stand now, it's not unreasonable to expect that future Ferals will continue to sport a mixture of druid-themed and rogue-themed leather alongside hunter-themed polearms, and the prospect isn't one likely to land us on Project Runway anytime soon.
I have to wonder if the continuing popularity of the warrior tank has anything to do with the fact that non-set plate tanking drops are almost universally designed to complement warrior tier sets. Blizzard has kind of a hearts-and-minds problem on its hands right now by insisting that it wants four viable tanks in the game while only designing gear that makes one of them look good.