MacCentral posts Apple's response to yesterday's Trojan warning from Intego.
According to the statement, Apple is investigating the issue:
We are aware of the potential issue identified by Intego and are working proactively to investigate it
Update: Wired posts more information on the purported Trojan:
[Intego] gave the impression that this is a threat, but it isn't," said Dave Schroeder, a systems engineer with the University of Wisconsin. "It is a benign proof of concept that was posted to a newsgroup. It isn't in the wild, and can't be spread in the wild. It's a non-issue."