Bungie's Frank O'Conner admitted in an interview that online co-operative play for Halo 3 might not happen due to development challenges. The developer did not rule out the possibility of adding the functionality at a later date, however.
"We're trying to make it happen," said Bungie's Frank O'Conner when asked by EGM if Halo 3 supports online co-op. "I think the biggest problem for us with online co-op is that we have a situation where you can be in a Warthog with five troops, almost a mile away from the other player. That's a significant challenge.
"There are lots of design things you could do to prevent that from happening, but they would make it not feel like Halo anymore. If we can make it happen in a way that works well, we will. And if it works badly, we won't," he maintained.
According to CVG, Bungie didn't rule out the possibility that online co-op could come at a later time via a downloadable addition.
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Thats a shame. I hope they can sort something out.
eh. it's not as much fun as sitting next to the person and hitting them when they snipe you
i never got into halo's story and i never played H2's co-op online.
i guess i cant miss what i never played. sucks for the hardcore halo fans though.
update: Halo 3 to Feature 4P Online Co-Op
The latest issue of Electronic Gaming Monthly caused a little controversy when Bungie couldn't confirm the existence of online co-operative play in Halo 3 because the feature wasn't ready. Now, apparently, it is. News out of a press conference in Amsterdam (as reported by Inside Gamer), later confirmed by former 1UP'er-turned-Bungie-mangod Luke Smith, brings word of four-player online co-op play over Xbox Live in the September shooter.
More details are expected on Bungie.net later today. Stay tuned.

just about to report that. Ah well,
The long-rumoured and eternally-desired Halo 3 online co-op feature is a beautiful, beautiful reality.
The news comes from a press conference in Amsterdam, where Microsoft announced that up to four (yes, four) players will be able to shoot, drive a melee attack through Halo 3's single-player campaign on Xbox Live. We can almost hear our social lives skipping off into the sunset.
Bungie's Luke Smith has since confirmed the news via the NeoGAF forums. "We'll have some more information on this and some details later today at Bungie.net", he promises.
Previously the company was refusing to commit to the inclusion of online co-op, telling US mag EGM "We know that people want it and we're trying to make it happen."
Fantastic news for Halo fans then. It's wonderful to realise that September is only a month away...
Did I mention "Coop FTW" ?

Well aslong as they make an update at a later date 'cause 4 way co-op seems quality
