HL2... I've only played the demo, but (when I'm not, you know, broke anymore) I'm hoping to have the full game soon.
DooM3 on the other hand... was exactly what I expected, but might have been more accuraty named DooM3D. No great plot (hey, like DooM1!), Mediocre character interaction. It corrected a lot of the issues from the original DooM, like the entire feel and design of the Mars bases and the whole vertical-scale thing. I spent the entire game wondering if I would have to wait til the next installation to fight the Baron of Hell... and then I found myself looking up, and up, and up... and noting the first actual EXPRESSION on the most anyone's face through the entire game as your security guard nearly wet himself. Speaking of security... you're a guy outfitted to patrol a closed base against human targets with similar equipment, so you can expect well-lit environs and thusly don't have weapons with built-in lights... or a light on your suit, like Master Chief (didn't the rescue force at the end have some kind of light on at the same time their weapons were out, however? Freakin elite forces, taking the illumination budget.) So, the flashlight thing made sense, as did the ten-monsters-or-less-at-a-time because the game mechanics would make suriving a twenty-Imp charge more or less impossible in the closed corridors until you got the bigger weapons. The closed corridors: perfect. You're on a base, exposure to the outside will KILL you, and suddenly the big nasty pink dogs and HellKnights are much, much (did I say MUCH?) scarier. Killing became an art - the shotgun (the spread of which isn't that bad, considering barrell length) is useful within a small range but within that is utterly lethal, the SMG is an excellent weapons for certain situations (spiders!), explosives had this beautiful concussive smack to them, and a single elegantly placed BFG shot can take out two of the mamma spiders at once. It's not about a grand fantasy scifi epic, it's about taking the minor detail that the Hellbeasts are after you and your Earth in a very *personal* matter, and applying proper force to counteract this.
Two last little fun things - yes, the majority of the game was a pattern, but the deviations are what are fun and freaky. The *SPOILER, sorta* spider crawling from behind something I was trying to use*/spoiler* was surprising and unwelcome, because I had just started a reload cycle on my SMG and all the other weapons were empty (big firefight, much splattering). Things like that, and things like little environmental interactions are what made the game really entertaining. Shooting cans. I shoot at cans a lot in real life, so when I found it was possible in game... well, guess what I did. Then I shot a can with the rocket launcher. I'm a bad man.