Well, the subtle effects may be more just personal preference or what one is used to. Change can be good but it can also be hard to adjust to. I think if i were to switch to acheivements from trophies I would like them less because I know what trophies look and sound like and though achievements are very similar they are slightly different and at least in the beginning my brain has to learn them. I think there is a natural aversion to unnecessary change as it takes up energy that could be used to keep us alive and our animal hardwiring doesn't like that.

bam! genetics causes bias.

This is a good point.  We all have biases, or we wouldn't be individuals. 

The difference between fanboys and gamers(I like to think I'm a gamer),  is that I don't let my biases rule me.

I'm not disagreeing with you, and as I noted above, evil was probably the wrong word to use.  I do think though that it's possible that folks could miss out on say a Gears, or a Valkyria, or an SMB, because their bias prevents them from owning a system, and that is too bad.

I understand that some can't afford (time or money maybe) all three, and this isn't about that, just the enjoyment of games on antother system as affected by your preference for one or the other.

It happens sometimes.

Well, its impossible to be completely unbias as you're only a human-being, so there will exist some bias and preference to one thing over another that can at times go completely against logical thinking. But, to be honest, from the sound of your post your critique seems mostly logical and down to experience of other games that exist on other consoles, which I think is a perfectly good way to critique games (as well as games on the same console of course).

pre this gen, i was a heavily biased Sony fanboy, lol

now, i own all 3 (+PC, i know you PC fanboys whine when i leave you out), i guess one could say my bias now is toward my 360, as i use it most and more games for it than the others, though, i did get my 360 in 2006, PS3 and Wii are both 2008 purchases, so to an extent its to be expected, my Wii game collection is relatively small but i play the games i have for it a fair amount, my PS3 game collection is also small at the moment, but GT5P gets some good mileage every now and then, i also watch many blu-rays on PS3.

of course, again as a nod to the PC fans among you, Football Manager 2009 is my most played game of the last year (infact, for any given year, the latest CM then FM is probably most played game)

i guess one could say i have a pro PC and 360 gaming bias, but without the implied anti Wii or PS3 bias, just that my bias toward the later 2 is less than the former 2.

I like what SciFiBoy said, I feel like I have a pro 360 bias but without a corresponding PS3 anti bias. I can completely understand why someone would like the games on that console better.

You're describing normal preference through experience, not bias IMHO. So relax you're a really good person!

Seriously though, what you describe is unavoidable. We all develop preferences based on experience and what it signalled for us.

So, for example, if you play FPS on 360 and find the triggers great, then play the exact same FPS on PS3 and find the controller only okay, that experience colours your view. Your brain simply informs your emotional response (sorry, sounding very Blade Runner here) and you cannot avoid feeling the 360 experience was somewhat better. Conversely, perhaps with a fighting game or platforming game, the experience might reverse, with your brain recording the PS3 controller and experience as slightly better.

Sure, if you really concentrate and put effort in you can theoretically overcome just about any learnt bias, but that can be tough - because in the end you may be trying to compensate for something real - i.e. perhaps the 360 controller really is just better for you. I think you're denying your own preferences to go that far.

For my myself, although I can now enjoy an FPS on consoles, either 360 or PS3, because I first encountered FPS on PC, and still play FPS on PC, I always find the console FPS just that little bit lacking. If only this was on PC, I can't help musing. I guess I could 'force' myself to cancel out my knowledge and experience of FPS with K&M on PC, but why?

When your bias in uninformed, driven by immaturity, overly competitive behaviour and is unfounded then you need to worry.

Just enjoy what you play on 360 to the max afforded by your set-up, and ditto for the PS3 - oh, and try out K&M on PC for FPS, it's even better... whoops, letting my bias creep in there!

@Reasonable that was very good post!

Sorry, folks, it was lunch time...some really good posts here.

I agree with everything said here; so I'd further the question to this: how then can we mitigate that bias when assessing the quality of games presented. NOT so much individually, but in our reviewers - you know, the ones we trust and even for those reviewers here (not saying anyone in particular has been bad)?