Excellent shot Emmanuel - plenty of good detail here, very well done.
The colours is related to colour space, the 2 most popular are Adobe RGB and Adobe sRGB. Adobe RGB has a far wider colour gamut. For serious imaging, you'd usually use Adobe RGB for all the processing side, and if you're uploading to a website, then you'd convert the image to sRGB, since web will not display Adobe RGB (well, let me correct that comment, most web browsers will *not* support Adobe RGB). FireFox 3 does, but you have to turn the function on in one of the config entries (about
:config in the address bar). You will notice some difference in colours between the 2 colour spaces.
As an aside, are you running a calibrated monitor? If not, I'd highly suggest doing so - it'll help set the black and white points for the monitor properly, as well as the contrast and gamma. It'll help ensure colour accuracy and consistency amongst your images.
Also, as a side note, most monitors are pretty crud, most LCD monitors use tn screen panels, which are notorious for having poor colour accuracy and tight colour ranges. Better quality panels cost more money, and use either s-ips or s-pva or mva. Most are ips/pva these days.
http://www.lcdpaneltypes.net/
I run a Samsung 245T 24" widescreen LCD monitor which has a better panel in it and thus, wider colour gamut and better colour accuracy. You can literally > ten thousand dollars on some specialist monitors too. They are super accurate, but you pay through the roof for it.
Dave
Now this is really really cool! 
