By now, everybody should be aware that an entity or cartel with the majority of the hashpower has absolute power over the network.

I read that article before. It is mistaken; users do not have voting power, because their only options are give in to the cartel or lose their coins. Note that any entity that can jam some process for a sufficient time can force the users of that process to accept anything that is not as bad as the jamming itself.

This paper is more correct, as far as I can tell:
http://hackingdistributed.com/2014/06/16/how-a-mining-monopoly-can-attack-bitcoin/

And here is my attempt to describe in more detail how the cartel could force a change of protocol that benefits miners:

http://www.reddit.com/r/Bitcoin/comments/2qdfat/without_downvoting_me_to_hell_can_someone_explain/cn5s41z
http://www.reddit.com/r/Bitcoin/comments/2qmfgw/so_warren_buffet_says_bitcoin_is_bs/cn82t3q
http://www.reddit.com/r/Bitcoin/comments/2qmfgw/so_warren_buffet_says_bitcoin_is_bs/cn7rxz1

Discussion of the "51%" risk often seem to assume that the attacker wants to either destroy bitcoin or to pull some scam, like a large double-spend, and then run away with the loot. However, monopolies usually try to use their power to maximize their gains in the long term, and are careful to not kill their cash cows -- which does not prevent them from doing many nasty things.