A few things to love:
1. I too have to say facial expressions. (Does anyone else see a resemblence in barney looking like Matthew Broderick?)
2. The Combine pushing you around...then later seeing thier blood splatter all over walls when you waste 'em.
3. The V-aliens voices
4. The Gravity Gun
5. It's completely different from Half-life 1. HL1 felt more like the trypical FPS. very little dialogue etc. This game has a personality...you feel more like a person in the game...less like a man with a floating weapon.
6. all the little things including the birds

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Things to hate:
1. That you have to be online to play (effing steam servers get too loaded)
2. Long Load times and jerky movement for about 2 seconds after
So far i give it a 9.3...it'll probibly be a 10 once i get some sort of shotgun

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P.S. does anyone know how to get out of the gravity room playground with alex and dog? Is there something special i have to do?