A quick over-view.
Halo 3 picks up right where Halo 2 left off. This is a good start for those who weren't so impressed by Halo 2's ending. The over-all story was pretty good. It cleared up most of what we have been missing out on. The ending was a bit open but conclusive, none the less. The dialouge is game was good. It kept me interested the entire way through. The story over all was pretty good but seems a bit short.
The graphics were impressive. I'm sure it's difficult to protray "real life" graphics in a si-fi shooter so it's hard to compare it to games like COD or any other realistic game. They manage to do a greay job, though. The lighting is one of the more notable upgrades from Halo 2. The way the light bounces of object, can result in some beautiful envirnments. The actually models of the game have been up-graded graphically, as well. They share the same high detail as the envinments. All around Halo 3 is a great looking game.
Gameplay in Halo always seemed to be pick up and play. The controls in Halo 3 are just that. There has been a minor change due to the introduction of deployable equiptment. The action/ reload button has changed to the right bumper button. It takes some getting use to but once you do, it's more natural then the old configuration. Also, the team talk button was changed to the d-pad which, like the bumper button, takes a short time to get used to.
Forge is basically a level editor. You can place weapons, spawn points, and basically any other object you see in the multiplayer maps. You can save these maps and play them as you made them. Also, while editting the map, you can change into a first person character and play the game on the fly. This helps to test things out that you just made. You can also play games in Forge with people switching between these modes. This is a feature that most people wont use but is very useful to some.
Saved films is another feature added to the game. Basically the game is saved and you have the option to view and save films of your matches. Even more interesting, you can go anywhere on the map and watch the match unfold. You can watch as you play, from a third person view. You can watch how your opponents played. This is a very cool feature for those you play on-line. Also, with in those films, you can save film clips. So lets say I got an overkill in FFA and I really wanted to save just that. I could go in, start recording, and only save that clip. The film feature also works in Forge and in the story mode.
Multiplayer is a feature that seems to keep the majority of people playing. There are many game types, ranked and unranked that you can play in. There are now speacial game types that'll pop up for the weekend like griffball and team melee. There is a ranking system that is effected by exp., which is just from playing any sort of matchmaking match, and your highest rank, which is the highest level achieved in a ranked playlist. This makes is so you can get match up with people at your skill level, plus it creates a whole new objective for the game.
Other new introductions to the series include achievements, four player co-op over xbox live, multiple armor permiatations, deployable equiptment, a few new weapons with the return of the assult rifle from Halo CE, new vehicles, a horrible map known as Isolation, and a few surprises along the way.
There are many other fine grained details about this game out there and are worth checking out but just from the list above, the game is worth every penny. The longevity of the game is high because of all these features. Definetly a great end, to what has been, a epic trilogy.