"Black snow" artifacts during AS maps flyby?

[Gian Paolo Mureddu]

    Hi all (yea, yet again another thing to report). I've noticed some 
"black snow" effect on various Assault maps during flyby. At first I 
thought it was due to my video card drivers (I was suing an ATi card 
with ATi's drivers 3.2.9-6), so I held them as the culprit. But I also 
noticed the _same_ effect on my friend's computer with a GeForce Ti4600 
and drivers 4496 and 4620. My question here is why do these effects only 
affect the flyby and not the rest of the map once you start playing... 
I'm curious really, since the "problem" does not cause any perfromance 
issues or crashes or futher artifacting...