The third and fourth issues of Marvel’s big spring crossover event, Avengers Vs. X-Men scored massive gains in circulation from issue #2, and along with the continued strong performances of the top DC top titles, many of which were aided by the Batman Night of the Owls event, helped the periodical comics category post a massive year-over-year increase in May.  Avengers Vs. X-Men #3 soared to an 11% gain in circulation over #2 (175,695 in May vs.158,650 in April), and Avengers Vs. X-Men #4 (178,330) also posted an additional gain in circulation over #3.  The monthly "battle" title AVX: Versus suffered a tiny drop (under 5%) from its first issue in April (103,436) to its second issue in May (98,819) and no fewer than nine of Marvel’s titles in the "Top 25" tied into the Avengers/X-Men event.
Marvel titles weren’t the only ones registering increases in circulation.  Scott Snyder’s Batman was up a solid 4,000 copies from the previous issue as the Night of the Owls event took off and the Justice League also saw its numbers rise as Jim Lee returned as penciller.  The Night of Owls event was also responsible for a spectacular debut for the Batman Annual, which came in at #6 with sales of 101,394, which is not at bad for a $4.99 annual.  The Batbook-wide Owl event also boosted the numbers of Detective, Batman The Dark Knight, Batman and Robin, Nightwing, and Batgirl.
The success of the Avengers Vs. X-Men and Night of the Owls events helped 13 comics in the top 25 post increases in circulation versus just eight that had decreases (four #1 titles debuted in May).  DC dominated the "Top 10" with seven titles to Marvel’s three, and the country’s oldest comic publisher put 16 comics in the "Top 25" versus nine for Marvel.
DC also dominated the graphic novel side with six of the top ten titles as it closed its marketshare gap with Marvel a little more in May (see "Comic Sales Soar in May").  The number of Robert Kirkman’s The Walking Dead graphic novels in the top ten in May was down to just three after a record seven in April.  But it is also interesting to note that the tremendous success of The Walking Dead TV show does more than just stimulate sales of graphic novels--Image's Walking Dead comic soared from #47 in April (36,931) to #28 in May (53,733).

The slowly fading memory of The Walking Dead’s monster second season did allow room for DC’s first wave of "New 52" collections to make the graphic novel charts. Interestingly in the comic market it was the Justice League hardcover that sold more copies whereas in the bookstore market in May, it was the better known Batman book that sold more copies (see "'Avengers Guide' Tops Bookstore Sales in May").  Also making the "Top 10" in the comic book market was Batman: Death By Design, an original graphic novel from uber-designer Chip Kidd.
While the Justice League and Batman hardcovers did sell the most copies of any of the "New 52" titles, it is interesting that the Animal Man trade paperback at $14.99 sold more copies than either the Green Lantern and Wonder Woman hardcovers.  DC’s Bob Wayne and John Cunningham recently discussed the reasons behind DC policy to identify the hot titles and publish collections of those titles in more expensive hardcover editions first before going to trade (see "DC’s Wayne and Cunningham on May Sales").  Speaking of deluxe hardcovers, it should be noted that the $40 deluxe edition of Watchmen made the "Top 10" list for the month before the release of the first Before Watchmen titles.
The top manga title was VIZ Media’s Naruto Vol. 56, which came in at #20 followed by Kodansha’s Sailor Moon Vol. 5 at #24.  This was the opposite order in which the two manga volumes finished in the bookstore market in May where Sailor Moon came in just ahead of Naruto, though the latter’s dominance in the more male-oriented direct market is to be expected.
Here are ICv2’s estimates of the direct market North American sales of the “Top 25” comics sold through Diamond Comic Distributors in May:
178,330           Avengers vs. X-Men #4
175,695           Avengers vs. X-Men #3
134,605           Batman #9
131,332           Justice League #9
101,394           Batman Annual #1
   98,819           AVX Vs. #2
   96,486           Batman Inc. #1
   96,016           Detective Comics #9
   88,796           Action Comics #9
   87,601           Green Lantern #9
   86,168           Earth 2 #1
   82,169           Batman the Dark Knight #9
   75,967           Batman and Robin #9
   69,265           Uncanny X-Men #12
   67,744           Avengers #26
   64,936           Wolverine and the X-Men #11
   64,326           New Avengers #26
   63,650           Wolverine and the X-Men #10
   62,807           Flash #9
   62,578           World’s Finest #1
   62,232           Superman #9
   61,395           Nightwing #9
   60,527           Aquaman #9
   58,710           Batgirl #9
   58,337           Amazing Spider-Man #686

For an analysis of the dollar trends in May, see "Comic Sales Soar in May."

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

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

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

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

For an overview and analysis of the best-selling comics and graphic novels in April, see"'Avengers vs. X-Men' on Top Again in April."  For an analysis of the dollar trends in April, see "Comic Sales Back on Track in April."

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