[Hmm, ok, well halfway through typing this I found that Anthony Burch also wrote about this last year.
Never hurts to have a second, less famous, less witty opinion though, right? .......RIGHT?]
My brother and I are red-green color blind, which is the most common and, as the name implies, means we have trouble with green and red the most, but it's definitely not exclusive to those, as purple/blue mesh together as well as brown/red/green, etc. Being colorblind has it's ups and downs, albeit way more downs than ups. The ups include getting out of certain science labs because I can't see the color spectrum properly and having it be understood when you aren't wearing "matching" colors. The downs are numerous, but not too extreme, but one of them is that gaming certainly IS affected.
I recently got a new computer, and bought Left 4 Dead (I already own it on Xbox) because I can finally run it. While tweaking some of the options, I came across something. Left 4 Dead on the PC has a "Colorblind mode" option! Making sure I hadn't overlooked it on the Xbox version, I quickly threw it in my 360. No dice. Why would something so simple be left out of the console version? I have no clue, but man am I glad I now own the PC version. While it's not game-changing, the things they do change are very much appreciated. Take a look at Bill being mauled by a Hunter in both options:
Original color scheme With colorblind mode on With my expert editing skills, I've pointed out the differences
With these slight changes, the game is just much easier to play. Things that should be instantly noticed now are. Not that I had a problem knowing when a Hunter was on Bill before, but the new white outline is a breath of fresh air regardless.
As for puzzle games, thankfully most of them have a colorblind mode, or have symbols on the things anyway (the exception I can think of being Bust-A-Move, which has NO colorblind mode). However, developers should be careful with which symbols they pick. For example:
Do I match up the T with the squiggles? Or the other squiggles with a T?
I can't play puzzle quest because it's just so confusing which things to match up. Hexic does a good job on putting various basic shapes
on their objects, and Bejeweled is nice enough to just use shapes to start with.
One game that fails in the color department is Overlord. It was the first game I bought for my 360 about a year and a half ago. I stopped playing it for several reasons, but I couldn't remember why.....until I tried playing it again yesterday. There are four types of minions in the game: red, green, brown, and blue. With the exception of blue, THEY ALL LOOK THE GODDAMN SAME. It's always easier for me to distinguish colors when nothing is moving and I can someone concentrate to notice any slight differences, but those conditions never really exist in games, especially Overlord when your minions are going all over the place. Not to mention the layer of brown all the cool games have over them for "realism!"
Speaking of brown realism, I love games that stray as far from that as possible. Rich, vibrant colors that stick out like it's nobody's business. This is one reason I bought Banjo Kazooie: Nuts & Bolts. I mean, just look at it!
Just looking at it brings me a smile of great color justice!
Mario games have also had a good track record of vibrant colors, and Nintendo in general, really. I miss the old days when they only had a limited amount of colors to work with and no one cared what "mauve" was.
Hopefully more (see: most) games in the future will include this option if possible. I can't see it being that much trouble, seeing as how it's just a couple color switches. Luckily, someone long ago decided that if two unnamed teams are going against each other, one is the Red team and the other is the Blue team, as seen in Team Fortress 2, 3v3 Arcade Hockey, and Supersonic Acrobatic Rocket-Powered Battle-Cars (all of which I play a bunch). All developers should adopt the tagline: "No rods, No cones, No problem!"
[Yes I realize that colorblindness doesn't mean we have NO cones/rods, but it makes for a catchier tagline, damnit!]