Do you have an specific glove model or a glove type in general you would recomend for using the N900 in cold weather ( taking in consideration warming factor vs. issues like destrexity reduction (both due to restriction of movement and fat finger syndrome), tactile perception reduction (feeling the bulges of the keys in the keyboard and the buttons around the device) and easyness of pulling out and using the stylus) ?

wow this is something i havent thought of! i live in cleveland and go to school in the middle of nowhere new york so its super cold in the winter!

one solution would be to buy a pair of mittens that allows you to remove the part that covers the fingers so that ur fingers are completely exposed so that u can type and use ur n900. i got a pair from american eagle and they are really comfortable for that purpose. they are pretty warm except for in below zero weather... i also have a pair of north face hard shell gloves, i dont kno where they are tho

edit: something like this:
kaboodle.com/reviews/womens-ae-convertible-mitten--american-eagle-outfitters

im a guy and they have ones for men. they're stylish too!

Greetings from Finland
Something like this:
http://img525.imageshack.us/img525/69/glove1.png
http://img440.imageshack.us/img440/2456/glove2.png


.edit
Hmph
http://en.wikipedia.org/wiki/S%C3%A3o_Paulo#Climate
I expect that you are going to use gloves in somewhere else. I would use swimsuit all the time if average temperature were that around year here in Finland.

I live in Finland as well where we get opur fair share of very cold winter temperatures.

In addition to the ones pictured in the post above, I've found that gloves that don't have the tips of fingers work very well. I live in the city so basically I'm always outting my hands back in my pockets or going indoors so its no biggie on the tips of my fingers.

However, last winter my fingers got really resiliant to cold because I wore those gloves all winter regardless of temperature. I was IM'n away at a bus stop at -20C no sweat (err, frostbite?). Good times.

does it get cold in brazil in the winter?

Sure, we don't get snow, but it does get cold enough to make any exposed skin significantly uncomfortable sometimes.