The whole Activision vs Infinity Ward heads debacle seems to cement in peoples mind that Activision have no replaced EA as the "Big Evil" of the gaming world, considering how often I've seen it mentioned as such in articles. I find this rather ironic, considering Activision got it's start from wanting to leave the original Big Evil, Atari.
For those who don't know, Atari was once the sole publisher of video games of the Atari 2600. Developers got sod all reward for games that sold well and zero credit to the developers. So in 1979, Larry Kaplan, Alan Miller, Bob Whitehead and David Crane leave the company to form Activision. IAtari attempted to sue their faces off during this time, but it failed.
We also have Atari to thank for the near death of the industry before it really got started. The history of the 1983 video game crash is an interesting part of the media history. The Wikipedia article gives a decent summary, with links to places which go more in depth:
http://en.wikipedia.org/wiki/Video_game_crash_of_1983Basically because they went after complete control, and trying to rush out half finished games to make a quick buck they nearly killed the industry...eerie how Activision seem to be trying a similar tack over Call of Duty some 27 years after the events that killed it's father isn't it?
That opened the way for the next "Big Evil," Nintendo. OK actually Nintendo were not really a Big Evil, more like a Big Brother by censoring their games, trying to be good but ultimately coming off like they think they knew better than we did about what we found offensive, at least. The following site has some very good examples of they censorship policies:
http://www.filibustercartoons.com/Nintendo.phpClassic example showing them taking out the crosses on gravestones and replacing them with the words RIP...in games like Ducktales:

More samples on Wikipedia:
http://en.wikipedia.org/wiki/Video_games_c...endo_of_AmericaGlad to see they no longer do this.
Then it seems EA came along and basically started dicking everyone around with questionable management practices, such as such as buying smaller studios who made great games then turning out shite sequels, buying shares in Ubisoft in what seemed like a potential lead to a hostile takeover, the "EA Spouse" thing and of course the whole "making really crappy games" thing. Again, Wiki has examples and links to more in depth stuff:
http://en.wikipedia.org/wiki/Ea_games#CriticismAnd my personal fave, when they tried to buy Take 2 in a hostile takeover:
http://en.wikipedia.org/wiki/Take_Two_Inte...Electronic_ArtsHowever, like Nintendo they seem to have done an about face, and focus more on making sure the products they release actually have effort put in and not trying to buy every single developer under the sun. Though this seems to be costing them money at the moment, I feel it will pan out in the long term.
And now we come to Activision who seem to have basically taken the Atari and EA model, and ramped it up to ten. One of my favourite examples, is when they bought Vivendi, cancelled a load of titles, including Brutal Legend, then tried to sue EA and Double Fine to stop them releasing it when they suddenly realise people actually wanted to buy the game (
http://en.wikipedia.org/wiki/Brutal_Legend#Publishing_issues), along with forcing the publishers of Ghostbusters and Riddick: Dark Athena to pay them some cash because they, again, decided not to publish those titles. Then there's them increasing Modern Warfare 2's price to £55 in the UK and so forth.
It also doesn't help that Bobby Kotick has a face that just screams to be hit with half a brick in a sock.

Personally I think Activision trumps them all considering it seems to remember it's own past, and seems to acre little for it's fans apart from treating them like cash machines. Yes EA did that but they seemed to have learned from their mistakes, whereas Activision just didn't seem to be paying attention to it's rival. Understandably I know these companies have got to make money but eventually people will turn against them even if they do lap up the odd franchise. It happened to EA, it'll happen to Activision. How that will pan out, who knows?
Maybe Ubisoft will be the next big bad? What with their odd new "you have to have the internet or FUCK YOU" DRM. That may be an exaggeration.