I don't believe the fight lasted 90 minutes for one fight. Maybe in total to get the boss down after a bunch of wipes and people doing that cannon afk thing, but not for one fight.
http://www.youtube.com/user/kclovesgaming <---- My Youtube Channel.
The length of the fight is obviously an exaggeration, but your point is that the person in the cannon was preventing you from completing the encounter.
This sucks to hear, but as many people suggested could have been solved easily by reporting him.
If all other 24 people reported him he probably would have immediately had action taken against him. Otherwise, you just intentionally wipe the encounter and kick him. Very simple solutions, and absolutely no reason to spend more than 10 minutes on it.
Once you realize he is griefing, instruct a wipe, and remove him.
That is why it is blatantly obvious that this is a gross exaggeration, but either way the point stands. This is not a problem blizzard needs to be concerned with, and can be addressed very easily. Even if the other 23 players aside from you had negative IQs, eventually it will dawn on them and with some proding in chat it should be quite easy to convince an intentional wipe. There are 3 options as well, so you wouldn't find it hard.
You can run way forward attempting to get to Juggernaut, and snipers will insta-kill you to prevent you from skipping the encounter.
You can run up the towers and jump off. The fall will kill you.
And you can run on the ships and dock behind the encounter's typical staging area and let the NPCs take the aggro. They will die and the encounter will end.
Once it does, you say "Kick XXXXXXX, he is greifing" and surely 5 of the other 23 will agree.
I regret to hear this happened in the game, but its time people use their brain and figure out how to deal with people, instead of just blaming LFR and Blizzard as if they don't have the tools to fix this already.
Correct course of action:
Stop tanking shit. Let NPCs die. Stop combat. Kick the dumb shit. Kill boss as normal.
I like ponies and I really don't care what you have to say about that.