I have by now while typing this only played a little more then 3 hours.

This is the best gaming experience I've ever played in the past years, I will wait 15 years agian for this game!

Edit:
There is a few things I miss from the other Half Life games, and that is the possible to melee a zombie in the head! So I really hope this will either be possible in the next game or a future update.

I hate that you always are low on ammo, I found out that ammo spawns they more you use the weapon.