Winner: Bungie

It's a no-brainer sure, but there is a plethora of reasons why this is a deal of a lifetime for the developer. First, it removes the shackles of Xbox 360 exclusivity, ushering in a newfound creative freedom for the developer.

All eyes are now on the developer to see what its 'next big action game universe' will be.

The deal will also give Bungie a chance to prove to the world that it is capable of a lot more than just Halo.

With the developer recently re-registering the trademark for its oher FPS franchise Marathon, could this be a hint of things to come?

Winner: Activision

Another no brainer, but why exactly? Activision is easily the most powerful games publisher on the planet. Chances are you may have saw their media blitz for a game called Modern Warfare 2 last November?

Whatever their next game, we're sure the combined efforts of Bungie's reputation as a developer and Activisions knack for making sure every person on the planet knows about it will lead to the game being the biggest media launch in history.

Winner: Gamers

Don't have an Xbox? Always wanted to play Halo? Well you still can't, but the deal means Bungie's titles will be ripe for the multiformat treatment.

Could their next IP be released on Wii, DS, iPhone, PS3 and PC? If you look at the multiformat trends of Tony Hawk and Guitar Hero, this seems very likely.

it means more of us gamers wil lbe able to enjoy the team's stellar work regardless of what format we own. Three cheers for being spoilt for choice!

Winner: Creativity

Bungie has come dangerously close to being a one-trick pony with Halo. Now it will have the freedom to do what it wants, when it wants and in any capacity it chooses.

Who knows? Maybe the developer will make a Wii, Natal or PlayStation Move game that uses motion control in ways we have never seen before?

This is a smart team we're talking about here, and it will be great to see how this new liberation will affect its creative output.

Loser: Microsoft

There was a time when Halo was a guaranteed console-shifter for Microsoft. While it still has control over the Halo license, it has lost Bungie, by far the most important part of the IP. 

Without the original creators on board, perhaps Microsoft will draft in a new third-party team to continue the saga? It's difficult to see how a new team could capture the essence of Halo quite like Bungie did, but then again we've been pleasantly surprised before.

Let's not forget the loss of guaranteed revenue. The profit made from the Halo series is not chump change and will surely dent the company's turnover.

Loser: Fanboys

The loss of Bungie as the sole Halo developer may result in a significant dip of quality in future instalments. If this happens, fanboys will have less ammunition for their flame war cannons. Which is always a good thing. 

Source

I don't lose or win until they create something good after bungie :P, Really I want them to make games PC first then consoles that would be cool, but I don't think that's gonna happen. Maybe I'm wrong.

Winner: Sony

to actually have a bungie game this gen....

Winner: Everyone since the game is now on 2 platforms and not one.

Loser: The soul of gaming I guess since Bungie chose Activision out of all publishers....

Well, it remains to be seen who the winner and losers are until Bungie produce something worthwhile on several platform and manage to sell it.
I hope no one expects them to make a game that will sell like Halo at any rate, that's hardly going to happen.

Come on... Do you call yourself a journalist without a five minute google.com reserach?

We know 343 industries will care about Halo. And a major Halo game (not an add-on (ODST) or spin-off (Halo Wars)) only releases every three years. So let them finish Halo Reach first, before we make any claims what the future of Halo will be like.

@DirtyP

You know, what you say about a major Halo game every 3 years is interesting...since this year we´ll see Reach, then if the trend continues the next major Halo game will be out in 2013...which would fit in perfectly with the next Xbox system.

So, either the next Xbox is released in 2012 with the next Halo coming out about 1 year later...or it´ll be a launch title for a 2013 release date for the new system...so we could be seeing the next Xbox being released in 2013 and not 2012..what do you think?

I'd say the chances of whatever this is hitting this gen are low. It's 2010. Even if this game only takes 2.5 years to come out, it'll be holiday 2012 by then, which should be the latest start of next gen, and likely is at least a year in.

@Mr Khan
Sony usualy gave 10 years to their consoles, i dont think 2012 could bring another new console apart from Nintendo new one. So if the ip comes in 2012 or even 2013 you coud be sure it will hit X360, PS3 or maybe (improbable) WII or there sucesor.

Could be. MS said the Xbox should last a couple of years, but I don't believe them. 2012 or 2013 will be the release of the Xbox 3.

I am a Halo-fanatic. I played every game with Halo on it and I am currently reading my second Halo book. But even I have to say that after Reach, which will be fantastic judging from the beta, we don't need another Halo game for some time.

2007: Halo 3
2008: nothing
2009: Halo ODST / Halo Wars
2010: Halo Reach

I think to treat the franchise right, we need a Halo break. A Halo 4 would be a sick system seller for the Xbox³, just like this gen.

Let's say the next Xbox launches holiday season 2012. If I were MS, I would play my cards like this:

fall 2012: Xbox ³ launch, some sports games, Rare games, CoD game

[If MS releases its console first, it will sell anyway for the first holiday season, because it will do stuff we haven't seen yet (360 launch - no great games but good sales and shortages). If it releases 2nd or even 3rd, you need a killer game to show the people what your console has to offer (PS3 - no games at first that showed what this machine is able to do).

2013: Halo 4 (system seller!) Forza IV,
2014: Gears of War 4 (system seller) Crackdown 3
2015: Fable IV (system seller)

This is pure speculation.