The Walking Dead topped both the Top Comics and Top Graphic Novel charts for 2012, according to information released by Diamond Comic Distributors today.  The bestselling comic of the year to comic stores was The Walking Dead #100, a multi-cover extravaganza that shipped in July, and the top graphic novel of the year was The Walking Dead Volume 1: Days Gone Bye TPThe Walking Dead’s chart dominance was near total for the graphic novel format, where TWD volumes took seven of the top 10 and  16 of the top 25 slots in the year-end ranking.  The Walking Dead Compendium, Vol. 1 was the top dollar graphic novel in comic stores in 2012.
Marvel’s Avengers Vs. X-Men and Marvel NOW! titles took the rest of the top ten comic slots for the year. DC had two Batman volumes (Batman: Earth One and Batman: The Court of Owls) and Top Shelf had one (League of Extraordinary Gentlemen III: Century: #3) to round out the top ten slots in the graphic novel chart.
Market share rankings were unchanged through #7, although there were some shifts in share percentages.  Marvel, which took the #1 share slot in comic stores, lost over 3% of share vs. 2011, as stiffer competition from DC and a two-point jump by Image made it more competitive for the top publisher in a growing market (final, year-end figures haven’t been released yet, but Diamond indicated that the final growth rate would be between 14 and 15%). 
The Big Two collectively lost 2.7% of market share to smaller publishers in 2012, wiht a 3%+ decline by Marvel not offset by a small increase by DC.
Image Comics gained over 2% of market share, primarily driven by The Walking Dead but also fueled by Saga and a generally good year.  
IDW Publishing gained nearly a point of share, with My Little Pony topping off a very good year for its licensed books, extending its lead over Dark Horse Comics for the #4 slot. 

Top 10 Comics in Comic Stores—2012
  1. The Walking Dead #100
  2. Uncanny Avengers #1
  3. Avengers Vs. X-Men #1
  4. Amazing Spider-Man #700
  5. Avengers Vs. X-Men #2
  6. Avengers Vs. X-Men #6
  7. Avengers Vs. X-Men #5
  8. Avengers Vs. X-Men #3
  9. Avengers Vs. X-Men #4
  10. Avengers #1
 
Top 10 Graphic Novels in Comic Stores—2012
  1. The Walking Dead Vol. 1
  2. The Walking Dead Vol. 2
  3. Batman: Earth One
  4. The Walking Dead Vol. 16
  5. The Walking Dead Vol. 3
  6. The Walking Dead Vol. 17
  7. The Walking Dead Vol. 4
  8. Batman Volume 1: The Court of Owls
  9. The Walking Dead Vol. 15
  10. League of Extraordinary Gentlemen III: Century: #3 2009
 
2012 Comic Store Market Share
  1. 34.06% Marvel Comics
  2. 31.94% DC Comics
  3.  7.31%  Image Comics
  4.  5.57%  IDW Publishing
  5.  4.81%  Dark Horse Comics
  6.  3.11%  Dynamite Entertainment
  7.  1.53%  BOOM! Studios
  8.  1.15%  Eaglemoss Publications, Ltd.
  9.  0.93%  Viz Media
  10.  0.89%  Avatar

For the top-selling comic boks by Diamond U.S. to comic specialty stores during the year of 2012, see "Top 500 Comic Books--2012"

For the top-selling graphic novels by Diamond U.S. to comic specialty stores during the year of 2012, see "Top 500 Graphic Novels--2012"