Some people claim that filing the springs of the micro-USB plugs will reduce the rick of breaking the socket. Is there any real evidence to support that hypothesis? Any factual data from an engineer who tests there things?

The springs in the micro-USB plug apply a force *inside* the socket, holding it in place.
Is the logic that this increases the force needed for insertion and removal?
It does not feel excessive to me, and because the socket is very low-profile, and snug to the board, the force transferred to the surface mount from normal insertion is small. And Nokia would have tested this with thousands of robotic insert/remove cycles.
I would be much more worried about sideways knocks to the plug while it is in the phone, e.g. from being dropped on a desk. The springs on the plug will make no difference to that.

BTW, older USB connectors have equivalent springs in the socket, but they can fail eventually, and its much easier to replace a cable.

The port on my N900 has been completely sturdy before (I think I received mine on 4th of december 2009), but couple of days ago it started to wiggle little bit sideways. There isn't any problems (yet) with battery charging or data connection, but I was wondering if I should get it fixed now before it gets any looser? I'd imagine it might be faster to fix now, as it probably would need just a bit of soldering.

I'm one of the early adopters. Last night it broke even if i KNEW about this and treated with extreme care mini-usb.

Sent email to nokia care.

I'm ****ed....

USB cable and charger filed down or replaced with smaller prongs???

None of the 2. I just unplugged/plugged it with care.

You should be okay - the European minimum warranty is 2 years.

2 days ago I got a new one. Repairing costs too much time, so I choosed an new one instead of repairing the old. A very long week without my N900.

Did you get any response from nokia? I'm going to buy an N900, but since I read about this isuue I'm concerned about how nokia care here in Italy deals with this kind of problem...it's really scaring me!

Is there anyone who already had this problem fixed here in Italy?

mine is broken to. I'm getting mad!!! i treat my n900 like a child!!!

Hi Santiago, I'm from Italy too!
Did you already get in touch with nokia care? Will they repair the unit? Thanks