Graphics: This criterion refers to how good the images look in a game and what makes them look that way. Titles which use high-color or 3D accelerated graphics, provide fast framerates (no stuttering), have good detail (crisp images as opposed to fuzzy), contain no distortions or glitches, have smooth animation, and provide good color depth and resolution get the high marks.
Interface:
Interface refers to how easy it is to configure and install a game, what kind of options it presents for self-configuring, etc. Titles that are easy to use, let you configure controls, and have good screen layouts for easy display get the high marks.
Gameplay:
Gameplay refers to all other game elements not covered by the other criteria -- those intangible aspects. How easy it is to play, how difficult/easy it is to do things (i.e., cast spells, switch weapons), how difficult/easy it is to control your character, delay between your actions and the computer's response, etc. Gameplay also includes the multiplayer aspects of a title. If the game supports Internet play or a specific service (i.e, Heat.net, MSN Gaming Zone), how fast the game is in multiplayer (lag), the number of players that are supported, how easy it is to setup a multiplayer session, etc. Most importantly, Gameplay refers to how fun the title is to play.
Multiplayer:
Multiplayer is rated based upon the number of players a game supports simultanously, what types of multiplayer action it supports (i.e., Internet, LAN), any changes in the gameplay from the single-player experience, game balance, setup and fun factor. Titles which do not have a multiplayer component are not rated on this criterion.
Sound FX:
Sound FX refers to the digitized sounds you hear during the game such as speech, weapons fire, etc. The more creative, realistic, and distinct the sound, the higher the score. Use of 3D sound such as A3D, EAX, DirectSound 3D are also noted. Also, points are given for sound depth, timing, quality, and appropriateness.
Musical Score:
Musical Score refers to the music (the score) you hear during the game. Points are given for creativity, depth, realism, timing, quality, appropriateness, and the general "feel" of the music. Also taken into account is whether the score adds or detracts from the game.
Intelligence & Difficulty:
One or both of these attributes may appear for a title, as some offerings do not offer one or the other. Intelligence refers to how smart the enemy is: If they will notice you and attack or just walk by, if they'll duck for cover or hide, and if they'll use tactics to outwit you, etc. Difficulty refers to how, overall, challenging a game is. For instance, if you can waltz right through on normal difficulty, then it's not too difficult! However, if you are slaughtered consistently, that game is rather difficult. This is more a measure for advanced, hardcore gamers who like a significant challenge.
Overall:
The Overall score simply refers to what the reviewer thought of the game. The above criteria can be deceiving given the fast advancement of technology, which while they are important, may not be representative as to whether the title is "good" or not. This criterion is meant to state whether the offering was poor, average, good, etc. based on if it was fun or not. Should you spend your money on it? That's what the Overall score is meant to help answer.