Javier, I don't know what G mail is but I'll do a search.
I've not been happy w/ what the G9 will do. Colors are often way off. It likes to see green fabric as blue. (It's fine w/ green grass.) I find the best color accuracy (indoors w/ incandescent light, or outdoors at dusk) to be WB - cloudy. Very strange!
I'm going to try setting the custom WB today w/ some white paper. It has 2 custom WB settings that are both adaptive, and the shop suggested using white paper (they didn't have a gray card) to set these. One for sunny and the other for dusk, as that's when I like to shoot. At dusk the G9 turns everything light (in Auto mode). I haven't really gotten an accurate dusk shot yet, and haven't heard any solid solutions for this problem.
The G9 does have a great feel, but certainly some serious limitations. I think it would have been a better camera at about 8 MP, as it does have some serious noise issues. But then again it will also do some very nice things.
At this point (w/ my very limited use of it), I will likely return it and probably wait for the next batch of cameras to be released. The shop said they expect something around Christmas or so. The G9 is a really nice camera, though I don't see it as something I will be happy w/ long term (at least not w/ the exposoure I have to it at this point).