Speaking of unintentional things going on in raids, it seems that Blizzard is finally taking notice that players really freaking hate being deceived and that the entire system is grossly flawed. Especially in regards to the duration of a lockout.
Those are all poo compared to the glaring issue of players being pretty much lied to and locked into an instance where a few bosses have already been killed. This has never happened to me because Im usually a bit manic, asking 20 questions if I ever join up a pug but for the most part its way too easy now to get duped into something.
Unintentional instance saving
We did speak with some of the developers about this recently. While Im unable to comment on your specific suggestions, Ill say we were all in agreement that something needs to change with raid IDs. On the one hand, we are happy that pick-up groups have a wider array of options at their disposal, whether it be 5, 10, or 25 man content. On the other hand though, its currently too easy to end up saved to an instance thats been cleared, or close to it, without knowing ahead of time this will happen.
Weve been looking at player feedback in this regard, and are working to develop a better interface to warn players that will be saved to an instance thats been partially, or completely cleared. This is something that might not happen in 3.1, but well be discussing this further internally in the near future. (Source)
The Battle of Mount Hyjal
Under Medivh's guidance, Thrall and Jaina Proudmoore - the leader of the human forces in Kalimdor - realized that they had to put aside their differences. Similarly, the night elves, led by Malfurion and Tyrande, agreed that they must unite if they hoped to defend the World Tree. Unified in purpose,
the races of Azeroth worked together to fortify the World Tree's energies to their utmost. Empowered by the very strength of the world, Malfurion succeeded in unleashing Nordrassil's primal fury, utterly destroying Archimonde and severing the Legion's anchor to the Well of Eternity. The final battle shook the continent of Kalimdor to its roots. Unable to draw power from the Well itself, the Burning Legion crumbled under the combined might of the mortal armies.