good to know there was a topic on this rattle.
yes. seems like i'm having this rattle too

 

Got it too on the driver's side. Just started at 900 miles.

 

I"m dropping off my car on Monday to get the B-pillar rattle and vibrating rear-view mirror addressed. I have a 2008 AWD model purchased about 2 months ago.

 

The problem is that on this site, there are several references to the B-Pillar rattle, however there are at least three sources of the noise.

1. B-Pillar noise is actually from the door seal, which can be resolved with 3M Silicone spray

2. B-Pillar noise is due to over-torquing of the door striker

3. B-Pillar noise is due to loose clips within the B-Pillar

The noise I hear occurs mostly over decently smooth roads but with undulations or slight unevenness. It also occurs over small bumps, but not so much so over larger ones.
The noise itself is a small, high-pitched rattling/clicking type sound as if several tiny plastic pebbles were being shaken within a plastic container.

My only concern is that I have correctly diagnosed the sound is indeed coming from the B-Pillar as recently I've had some doubts as it's coming from the general passenger side area and could possibly be something within/under the seat or inside the door as well. I do not think it's coming from the passenger dash though, but I could be wrong.
I just hope the tech I work with will either know of this issue or will hear it and diagnose it correctly!

 

the dealership 'fixed' mine, but the noise was only gone for a day. i feel it also has to do with the seat position. when the seat is further back, the rattle is there. for short legs, the rattle is not there. the noise is back after $370 warranty repair. they did lube the sunroof though!

and my glove box rattle is still there, as i didn't ask them to solve that yet.