I enjoyed it. I played through it twice, and beat the expansion once. It was hardcore in tone, which made it almost uncomfortable to play, but then you get in a massive firefight and it relieves the tension for a while.
I think most people who disliked it were expecting a game just like the previous 2, which I guess is a fair expectation to have. Doom 3 is certainly not like those games, for the most part.
I gave up on expecting sequels to be more of the same a long time ago though.

I loved it, and I still love it. Granted... ID (or iD if you prefer) is also my favorite development company...so... what else can I say without being uber biased.
I'm also kind of a sucker for that "dig-site-artifact-turns-out-to-be-million-year-old-demon tool/spawn-gate" story line which, come to think of it, is in every iD game in some form or another...

It's an okay game. Technically impressive when it came out and still the same despite the years, but it follows the basic formula of the roller-coaster that so many games follow, including the overrated Half-Life 2. The spawning monsters as soon as you get goodies worked in the original Doom or the first two Serious Sam games, because these were mostly about constant action, but since Doom 3 tried to be more atmospheric it kind of fell flat. Still there were some nice touches, like the monsters eye glowing in the dark, and the audio was generally very good and helped to get the tension up, until you knew that as long as you did not move no enemy would come and get you. It's a bit sad that it tried to go half between a classic corridor shooter and something like System Shock 2, while achieving none of those game's full potential. Still a nice way to spend your week-end at night, I guess, but not worth the hype.
But at least Doom 3 didn't try too hard to shove its pretentiousness down your throat by attempting to have you care for paper-thin characters, because it at least admitted that they were expendable. The absence of adolescent ego-stroking was also somewhat refreshing. While Half-Life 2 is just as mediocre as Doom 3 — and maybe even worse because it is really too easy even at the highest difficulty while Doom 3 in hard is much more challenging — it is unfairly hyped to kingdom come as the perfect mix of narrative elements and gameplay. As if ...

I'll just re-post this again in case anyone missed it.
It's worth replaying Doom 3 for, especially if you hated it because of monster closets. Monsters will come out when you're not expecting it, and you can expect to do a lot of running when your ammo stack is dry. Who knew those annoying imps could actually be scary?
Don't believe the other mods when they claim they have made Doom 3 much closer to the first 2 games. This mod is the real deal.

Sounds good! Thanks for the link.

Why does it say the purpose is to make the game "more massive and multiplayer-like?" What does that even mean?

I thought doom3 was good. and people who diss it tend to forget how stunning the graphics were at the time... it truely was a generational leap.
That said... it wasn't what i was expecting. It was essentially a survival horror game... and i was expecting a doom game. Doom 1&2 weren't remotely scary or horror, they were about blasting dozens of demons while dodging fireballs in sureal, but large open environments.
As such, i think Serious Sam and Painkiller were closer to catching the feeling of doom... though i don't think either quite nailed it.
Oddly, the only real mechanic they kept from Doom 1&2 was the one they got criticised the most for.. the monster closets. Dozens of monsters appearing when you picked up an armour was always a doom staple.
While i think it's unfairly criticised... i must say i palyed Farcry right after doom3, and loved it much more.

I think what was implied was that the pacing was much faster. Doom 3 leaned towards the "realism" side a bit more by making everything slower, such as run speed. In Ultimate, the pacing is just breakneck - this does not mean you can easily outrun enemies though, but the overall pace can match up with the older Dooms.
Some of the problems I had - as in difficulties with the mod, not technical issues - were that you would run out of stamina very quickly, not because it's been tweaked, but because you find yourself really having to use Sprint very often. Also, monsters have been tweaked eg. the Imp now fires very fast moving homing fireballs that makes it mandatory to sprint in order to avoid. And then there's the whole issue of ammo becoming increasingly scarce as the difficulty ramps up...
All in all, it makes the game feel like something else entirely. In fact, even though I liked the original Doom 3, I'd say this should have been what the game was when it first shipped.

That mod just completely fucked up the aspect ratio or something. When I first started, the mainmenu was halfway off screen, and everything was upside down. Everything after, and the entire thing is sort off skewed, so that I can only see most of the lower right corner, and the mouse' location is not where it's shown.
Apart from that it seems quite interesting.

Thanks. I will try this out after I finish some of the games I'm currently playing.
So what's up with the monster spawning? Is it like Doom 1 on Nightmare mode, where they just keep respawning everywhere, or is it more scripted than that?

I am playing blindly all id Sofware's games. So all games that id did, are epic for me.

I kind of have to agree. HL2 was a very well executed, but utterly generic shooter, that as a bonus made me nauseous. I liked it better when it was called Breakdown, was fun, and didn't make me physically ill. On balance to the Orange box, Portal was fantastic, though.
I don't know if you're being sarcastic or not. If not, did you play Quake 4 and Prey? Prey is fantastic. Not ID, but in the ballpark.

I never really paid attention, as I only played it once through. I don't know how dynamic/random it is. All I do know is, I got caught off guard many times by spawns that I never expected. I mean, I just stood in one corner, reading my PDA, and all of a sudden, I get mauled by an Imp.
But yeah I can liken it to Nightmare on Doom 1. It is possible, though, that they will eventually stop coming, but I was too busy running for my life to actually ponder over that issue lol.
I forgot if the mod did that to me, but some mods have the tendency to do that. I think there may be a left over .cfg file or something, try removing that and see if it fixes it.
Either that, or your version is incompatible. Try updating to version 1.3 to play it safe, rather than 1.3.1

I agree. I love the cheesiness of it, and how they just don't care if it's the same old thing.
Rage doesn't have it though, does it?

As far as I know from the little details no. However, who knows. With iD the "space marine" could probably just portal in and be like "Oh hai guys" at any point in the game and it would be totally canon.