QUESTION:
I remember reading on a NASA site that Cassini arrived at Earth a day
earlier than expected after the 2nd flyby of Venus and they couldn't explain
why.  Is this correct?  I cant find the information anywhere anymore.

ANSWER from Tom Spilker on September 20, 1999:
Cassini's Earth flyby milestones occurred 0.6 *seconds* later than scheduled.
Since launch, the spacecraft has always been within a few kilometers and a few
seconds of where we expected it to be.