Marvel’s weekly mailer to retailers went out today and buried in it was a little item that read as follows:

10% EXTRA FOR FREE ON MARVEL UNIVERSE JANUARY SHIPPING TITLES!

As a thank you to Retailers, Marvel will be sending an additional 10% of FREE copies for all of January shipping Marvel Universe titles! For all orders made by FOC, Marvel will be sending 10% extra at no cost to Retailers!

Which sounds…nice? But also could have ramifications on many, many things, from our sales charts to Diamond’s publisher rankings.

It’s no secret that Marvel and DC have been locked in a battle for the #1 publisher for a while – with Marvel usually winning but DC taking the crown for six months. Since Diamond’s charts are based on what hey ship to retailers, this extra 10% might be included in unit and dollar market shares…giving Marvel a little boost. Even if a store ordered only one copy of something, they are getting an extra copy, doubling shipping in some cases.

UPDATE: I have been told by a Marvel spokesman that this 10% will NOT be counted in Diamond’s number. That is consistent with how Marvel handles overships on other product launches.

Marvel NOW!’s performance with readers remains one of the biggest problems facing retailers, as enthusiasm has been patchy and nothing has really caught fire. Even if this overship is not counted in the monthly charts, having extra copies on sale to sell to readers is a proven sales booster in many cases.

Any retailers out there want to chime in?