On the 2nd July, prolific supernova discoverer (76 now from memory) Berto Monard from South Africa discovered a magnitude 16.6 supernova in M66 (NGC3627) catalogued as 2009hd.
M66 has had 3 previous supernova - 1973R (mag 14.5) discovered by Rosino. 1989B (mag 13) discovered by Bob Evans and 1997bs (mag17) discovered by LOSS
Interesting to look at the list of prolific supernova producing Galaxies over the last 100 or so years.
NGC6946 = 9 Supernova,
NGC5303(M61) & NGC5236 (M83) = 6 Supernova each
NGC2276, NGC3690, NGC432 (M100) = 5 Supernova each
10 Galaxies with 4 Supernova (including the above discovery)
26 Galaxies with 3 Supernova
161 Galaxies with 2 Supernova
Would certainly be worth imaging M66 with its new "guest star" and perhaps submitting a colour image to The Bright Supernova page as we don't often see nice colour images there (link below). It is quite possible the supernova may also brighten.
http://www.rochesterastronomy.org/snimages/
PeterM.