Perfect sequel to the best FPS ever made.
Gameplay - With some of the best FPS action ever, gameplay is a sure 10. With a perfect blend of fast action and an intriguing story, HL2 delivers as a must-play FPS.
Graphics - As with all PC games, this is dependent on the system you own. The way I judge this is visuals VS performance. How well can the game be ran on a mid-range computer, but still look great? Half Life 2 is one of the best for this. On medium settings at 1280X1024 the game looks near perfect. With that being said, the game on max settings, AA enabled and 1680X1050+, is possibly the best to date.
Sound - The right sound at the right time. Deep basses on explosions. Great ambient sound. Voice acting is crisp and clear and very well done. Music really gets the blood pumping. You know when something cool is about to happen when the awesome music starts up.
Value - I'd say this is the strongest point. You can play through the game on medium setting, and the game is fun enough to come back and play it again on hard. The biggest strong point of HL2 is the modding community. CS:S is possibly the most popular online shooter in history, and is run off of the HL2 engine. Between CS:S, HL2DM, TFC:S and the many many other mods, the re-playability of the game is endless.
Reviewer's Tilt - I've played many, many FPS games in my gaming life, and none have brought me into a story so quickly and so brightly as HL2. From the beginning I was sucked in, ready to see what waited beyond every corner. Playing this game was truly a great feeling.