To be completely clear, in an effort to avoid confusion, this change is currently only active on the patch 5.3 PTR, not on live servers. What's more, it only relates to Rated Battlegrounds. This is not applicable to random battlegrounds.
With that housekeeping out of the way, there's something else that everyone should know when assessing the weight and purpose of this change, which Brian Holinka clarified via Twitter shortly after the patch notes were released.
.@ecapsecaf Something to keep in mind is that in RBGs flag carriers were taking an undocumented 25% extra damage. This is 25% increase- Holinka (@holinka) April 15, 2013
What does this mean exactly? As soon as any player was carrying the flag in a rated battleground, they took 25% extra damage. This had not previously been documented. So, taking the change in that context, basically, as Holinka puts it, everyone who isn't a tank will take 5% less damage than they used to when carrying the flag. Tanks will take an additional 25% damage.
So, the question is as follows: why are the developers doing this? What is the purpose of these changes? Some have speculated that they relate to the potential issues arising with PvE gear being the best choice for PvP tanks come 5.3, but this isn't the case. Holinka confirms this on Twitter:
What's more, this change wouldn't specifically address that issue, as its simply a flat across-the-board increase to damage taken as a flag carrier in a tank spec.
Rather, what the devs are aiming for with this change is a reduction to the need for tanks as flag carriers in rated battlegrounds. Why is this specific to rated battlegrounds and not random battlegrounds? We can't be entirely sure, but it likely relates to higher levels of organization in rated battlegrounds, and, again quoting Holinka on Twitter, "It's a bigger problem with a flag carrier just standing in there with 2-3 healers in RBGs". The issue of "unkillable" tanks has been around for a while, and this change looks to help address this.
It also aims to make more different specs viable flag carriers, removing the requirement for tanks in capture-the-flag battlegrounds. This has been confirmed twice by Holinka, with Ghostcrawler throwing in his 2c, too. Ghostcrawler's tweet notes that the team still wants tanks to be useful, just not required.
Is that really a bad thing? Will it mean that tanks are "meaningless" in rated battlegrounds? Not according to Holinka:
But a big nerf to a specialization's primary function in rated battlegrounds is unlikely to be looked upon favorably. Holinka points out that the nerf may still require tuning, but it doesn't look too likely that it will be dramatically altered, at this point at least. It seems something of a shame that one of the "trinity" of specs is taking such a focused nerf in this area of PvP, but many argue that it was sorely needed. What do you think of this change? We will just have to wait and see how it pans out, and test it on the PTR!
If you haven't yet, hop on the PTR and get PvPing. Full Tyrannical gear is available for gold (which is free on pre-made characters) from the giant Flaskataur in the Shrine of your choosing.