Ah, the good old Mac Vs PC debate rears its head again...
I've had no problems either at home (on a Linux box or my Vista laptop) or at work (but seeing as I work for the MOD that's probably no indication of it being secure at all
).
Could it be malware that has "been and gone" and some people have been unfortunate to be on here at the time and downloaded it (not through choice though)?
Ian