This would be very cool if it happened. I still remember spending all of my childhood after learning to read waiting for Comet Halley to return, and then having difficulty seeing it even in the desert of Arizona. Now I refer to that comet as "Halley's Smudge." Comet Hale-Bopp was all right, and well visible from Boston Common on a fine spring evening in 1997 when I was there on a business trip. Simply put, predicting the visibility of a comet to the naked eye is more wild guess than science, but when a comet is visible, it is a delight to the eye.
AFTER EDIT, EXPLANATION OF ASTRONOMICAL MAGNITUDE SCALE:
Oddly, the historically developed magnitude scale (which goes back to the ancient Greek astronomers) has the brightest objects ranked with magnitudes that are negative numbers, and dimmer objects ranked with increasing numbers that eventually become positive numbers. Of course the estimate of eventual brightness of the newly discovered comet is just that, an estimate, and may disappoint.
FYI the Greeks didn't have negative numbers. Philosophers were still arguing whether zero could truly be a number (there wasn't really a need for zero as a placeholder regardless, Greek numerals don't have a positional aspect).
AFTER EDIT, EXPLANATION OF ASTRONOMICAL MAGNITUDE SCALE:
http://outreach.atnf.csiro.au/education/senior/astrophysics/...
http://www.icq.eps.harvard.edu/MagScale.html
http://csep10.phys.utk.edu/astr162/lect/stars/magnitudes.htm...
http://www.skyandtelescope.com/howto/basics/Stellar_Magnitud...
Oddly, the historically developed magnitude scale (which goes back to the ancient Greek astronomers) has the brightest objects ranked with magnitudes that are negative numbers, and dimmer objects ranked with increasing numbers that eventually become positive numbers. Of course the estimate of eventual brightness of the newly discovered comet is just that, an estimate, and may disappoint.