Comic sales in comic stores were down 4.4% in September 2012 vs. the year ago period, when the New 52 #1s were rocking the market, according to information released by Diamond Comic Distributors.  While the DC #0s in September 2012 were successful enough to take nine out of the top ten slots on the top comic chart for the month and drive DC to a 5% market share win, they were not enough to beat the #1s last September. 
DC’s market share win was substantial, 36.4% vs. 31% for Marvel in dollars, and 41% vs. 33.7% for Marvel in pieces.  Marvel did take the #1 comic slot with Avengers vs. X-Men #11.
Graphic novels were up a healthy 14.4% in September over September 2011.  Marvel also had the #1 graphic novel with the $7.99 Thanos Quest #1 (this reprint is not really a graphic novel but bound in the traditional comic book format).  DC had four titles in the top ten, starting with The Judas Coin HC at $22.99.
The total of comics and graphic novels was up only 1% vs. September 2011. 
Year to date sales comparisons to 2011 remain robust, with comic sales in comic stores up 17.1%, graphic novels up 14.2%, and the total of comics and graphic novels up 16.2%.
Quarterly numbers were also released. Q3 sales were up a less robust 8.3% for comics, 7.8% for graphic novels, and 8.1% over-all, primarily because of the September numbers and the tougher comps for Q3 2011.  
The fact that year over year numbers remain positive despite the extraordinary month the market had a year ago in September 2011 is certainly a positive sign.  The big question going forward will be how Marvel NOW! titles are received.  Avengers vs. X-Men is ending in October, and the rest of Marvel’s line appears to be in a slump in the run-up to the new titles.  If Marvel NOW! has a strong reception, the market can continue to grow.  Without a strong reception, it’s going to be tough regardless of how well DC does.

For an overview and analysis of comic sales in September, see "'Zero' Issues Spark Market in September."
For our estimates of actual sales by Diamond U.S. from comic specialty stores on comic books shipped during September, see "Top 300 Comics Actual--September 2012."

For our estimates of actual sales by Diamond U.S. from comic specialty stores on graphic novels shipped during September, see "Top 300 Graphic Novels Actual--September 2012."

For our estimates of actual sales by Diamond U.S. from comic specialty stores on comic books shipped during August, see "Top 300 Comics Actual--August 2012."

For our estimates of actual sales by Diamond U.S. from comic specialty stores on graphic novels shipped during August, see "Top 300 Graphic Novels Actual--August 2012."

For an overview and analysis of the best-selling comics and graphic novels in August, see "'Avengers Vs. X-Men' Finishing Strong."  For an analysis of the dollar trends in August, see "Bull Market in Comics Continues in August."

For our index to our reports on the top comic and graphic novel preorders for January 2000 through September 2012, see "ICv2's Top 300 Comics and Top 300 GNs Index."