Is Halo 4's multiplayer different from what you remember? In some respects -- new weapons and armor, call-in ordnance drops, map markers that show where special weapons are located (and when they disappear) -- yes, it is different.
But it's also still a really polished game, with fun maps and an enormous amount of customisation options for both your Spartan as well as your game and what mode you're playing. And if you're still not satisfied, you can create whatever honour-based rules you like in your own set-up in Forge mode.
To give you a sense of what the multiplayer feels like, above is a montage video of me killing people a lot. I know I'm not the most amazing player you've ever seen. If I was, I would be streaming every moment of my game-time on Twitch.tv instead of plastering it here for informative purposes. In fact, here's a montage of me dying a hell of a lot too.
Whether it's from being silly and trying to use the Warthog to ram into people at an awkward angle, or from freaking the F out when being attacked by a fast-moving Flood enemy, or, hell, this being the first time I got my hands on the game, I am definitely not immortal. Feel free to poke at my immortality.