Maybe not my latest disappointment, but probably my biggest... Dungeon Keeper 2. Yes, it's old news, but the scars haven't yet healed for me...

A close second place goes to Evil Genius.

And, just off topic a little, I personally love Left 4 Dead, but I would point out I got it when steam had its half-price weekend. I feel it's fantastic value for $25, but with a tiny spread of weapons, levels and items, I can see why people felt a tad underwhelmed. It probably doesn't hurt that I only fire it up when friends are online either...

Edit: And yes, bring back adventure games!

Hellgate London has to be in there somewhere. Few games have so enraged players that they created their own site on which to vent their spleen! www.flagshipped.com

But Master of Orion 3 is at the top of my list for disappointing, as released.

It seems to me that developers start out on a sequel by saying, "Ok, now what do players really like about the game. These things? Right then, let's take those out and do something entirely different."

I'm  still shocked people actually purchase those  SIMS  games.  Well I can understand some females possibly being interested with playing Ken and Barbie on the computer.

Sacred_2  has been a disappointment for me... the only interesting piece for me was fighting the final boss in gold with a hardcore character where your heart starts racing.  Overall  there's no real game depth... all map monsters die within two or three swings.  Currently playing this game brings as much joy as going for a walk around my neighborhood.

Diablo_3...  I hate to say this, but I have a bad feeling Blizzard is making some bad decisions with its development... such as with the  ORBS.   I really hope I'm wrong.

MoO3- Need I say more

Spore - had so much potential but was ruined by the dumbing down they did of it.

Star Trek legacy - They blew the budget on voice actors

Well.  I am female. But was after LCP more than Ken and Barbie   Hopefully Sims 3 will actually be more of a sandbox or have that mode either builtin or via trainers.

Oddly enough I played through Diablo 1 like crazy, loved it.  Played LAN, online you name it.   Bought Diablo 2 and it's expansion when they were bundled together.  Never once completed it.  I just didn't get on with the thing.   I was dissapointed but hey we're all different.

Anything dealing with LOTR.  I want that big epic battle experience but nothing has met my expectations.

Dawn of War 2. If you're going to release a game...finish it first please! And it has such god aweful netcode you're lucky to get 50% of your 3v3 games finished without someone suffering the connection flood and dropping. Not to mention Steam -AND- GFWL being required. And where are my destructable bridges?

I guess I'm a "sheep" - I don't mean to troll, but I found that comment rather obnoxious - just because you enjoy something that many people like doesn't mean that you have no individuality. Also, I enjoyed Oblivion, Fable II I also really enjoyed and L4D is another fun one.

I agree with people about Spore - I got to the tribal stage and found what appearing to be a very cut down RTS that had such limited units, and such a low unit cap that there was no real way to get supremacy over your neighbours.

Big dissapointment. I played it for about 3 hours, and now it sits, unloved in my Games Rack.

• Daikatana - nuff said
  
• Star Wars: Jedi Academy - As compared to Jedi Outcast, crap. single player: boring, no atmosphere; multiplayer: hit detection was off and the red/strong style jumping attack was made useless
• Final Fantasy XII - kudos on the new battle system, but virtually no story, characters have no depth

I wouldn't list Oblivion on here, but I enjoyed Morrowind much more. I did get tired of fighting bandit after bandit, each wearing one-three pieces of elite Glass armor. I really felt like once you'd seen one cave, you'd seen them all. Basically, after doing all the Qs for mages, fighters, thieves, assassin guild, arena and a few shrines, I completely lost interest in Oblivion.

As for D3, I think it'll be great. Apropos the orbs, I think their rationale for it (force in more strategy/thinking to the fighting) makes sense. In any case, there will still be potions.

After reading many replies, I have to throw in for MOO3. I followed that game's development like a stoner followed the Dead in the 80's. Every minute tidbit that came out, I was frothing at the mouth over. When it came out, I played it for maybe 3 hours before I got too bummed out and stuck it in a drawer somewhere.

When I randomly came across GC2 a month after it came out while in Brest Buy, I began playing it and it was as if the crashed and burned moo3 had risen from its ashes as a phoenix named Gal Civ2. When i still played WoW, GC2 took many hours away from that. Hmm, play a fun space game, or grind honor/ sit around waiting to do bg's.

Is Diablo 2 a sequel that you need to have played Diablo 1 to enjoy? I havent' played either, but I'd like to start playing Diablo 2. It can run ok on XP right? I have some older games that won't so I'm not sure. Also, probly buy it on ebay or something?

EDIT: I'm so glad i did a lot of research before i purchased Spore. Because that way, I DIDN'T BUY IT lol.

My last big disappointment?

Demigod. No contest. I really don't like the game. Honestly I consider preordering it my worst choice in years.

Oh, btw I'm all with Haree78 about L4D.

I love it. Best 2008 PC game in my opinion.

It's clever, polished,  well tought, it looks good, it doesn't bother me with insane requirements and, god, it's fun as fuck if played with three friends on expert.