Comet Ison may be visible in daylight during a rare total solar eclipse, today Nov. 3...

"There is going to be a Solar eclips on November 3, 2013 — within 24 hours of ISON’s first, i.e., inbound, crossing of Earth’s orbital path.
The eclipse will be total for some.

For others it will be ‘annular‘, i.e., the outer rim of the Sun will be seen around the moon. Hence why it is called an ‘hybrid’: total for some, annular to others and partial to some others.

Looks like we in the eastern US will be in the annular/partial corridor  Either way, the chances are that many might get to see C/2012 S1 (ISON) during the day, a month ahead of its possible daylight visibility close to perihelion on November 28."

[link to cometison.wordpress.com]