The remake of 1998's Metal Gear Solid was developed by Silicon Knights and published by Konami in March of 2004 for the Nintendo Gamecube.
The main complaint that players had of the original Metal Gear Solid was that it had overdone the cutscenes and codec conversations a little, putting in too much time where the player must simply sit and watch. And so players hoped the next game, whenever it came, would minimize the plot elements and focus more on the gameplay. When Metal Gear Solid 2 came out, and focused even more on the non-interactive parts of the game (and also didn't have the player play as Solid Snake for most of the game, and also had a plot that made no fucking sense), many players felt betrayed. The reaction of many was: why couldn't you have just put all these new features in MGS2 (which are quite nice, thank you) into a game that was much more like MGS1?
And so Silicon Knights did just that in Twin Snakes: they took all the major features of MGS2 and put them into the plot and world of MGS1, and also jerked the game's graphics into the current generation of consoles.
The biggest new feature is the vast improvement in the AI. No longer are the genetically engineered soldiers of the Next-Generation Special Forces (with their heightened senses and reactions and so forth) dumb as bricks and so very easy to get the drop on. If you hide somewhere after being seen, they won't just wander around aimlessly hoping to see you; they will systematically search the many hiding spots of the area. If you kill one of them, the body won't just disappear, either: it will stay on the ground, and the alarm will sound if someone spots it. Hide those bodies!
Also included is the M9 tranquilizer gun. This allows you to knock someone out from a distance, with the added bonus that if someone spots the body, they'll just kick them and wake them up, rather than sound the alarm. Later, you find a sniper rifle version of this gun, letting you put them to sleep from a much greater distance. The effect this little addition has on the gameplay is tremendous: not only will the alarm not sound if a guard discovers a body of a sleeping comrade, but it won't even sound if you hit a guard with it and he doesn't fall asleep right away (he'll merely go "huh?" and wonder what that prick was).
The one fault I can find in this remake is in the voice acting. All of the dialogue has been redone, as far as I can tell, and though all of the cast members they got back are as good as they were the first time around (which include nearly all of the major characters), and though many of the new voices on minor characters are just as good as before, there is one blemish: the new voice for Dr. Naomi Hunter.
Naomi is one of the main characters, and also the one with some of the most powerful (or sappy, take your pick) dialogue in the game. In the original, the voice actress did a pretty good job of playing the scientist who is by turns businesslike and emotionally detached and pontificating about the meaning of life. The new actress just sounds bored which makes listening to her boring; bored people are boring people.
All in all, however, Twin Snakes is probably the definitive Metal Gear Solid experience, and should be added to the small but growing list of must-own Gamecube titles, especially if you've never played the original.