The Diamond Comics Advance Reorder List is a great speculator tool. It shows what books retailers are going back to get more of, in advance of their release. They are actually putting their money up betting these books get big. These are the books people are talking about in shops, message boards, and websites. Here is the Diamond Comics Advance for 7/9/18:
Crush crushes the list as Teen Titans #20 regular and variant take two of the top four spots. Cosmic Ghost Rider goes back for a second print, Venom #1 goes back for a 3rd. Oddly enough Infinity Wars Prime goes back for a second print weeks before it is released. Thor #1 goes back for a second print with two variants, a Ward Variant and a Wolverine Variant. DC sees reprinting on Teen Titans Special #1. Joshua Middleton remains popular, his unique cover for issue #25 ranks high for DC. Justice League Dark and Mr. and Mrs. X are the new series being ordered. Wonder Woman #51 has an Artgerm regular cover! Looks great. The full list is below.
TOP 25 ADVANCE REORDER COMICS/GRAPHIC NOVELS/TPS
TEEN TITANS #20
INFINITY WARS PRIME #1 GEORGE PEREZ VAR
AMAZING SPIDER-MAN #2
TEEN TITANS #20 VAR ED
VENOM #4
TEEN TITANS SPECIAL #1 2ND PTG
INFINITY WARS PRIME #1
BATGIRL #25 VAR ED
VENOM #1 3RD PTG STEGMAN VAR
WONDER WOMAN #51
COSMIC GHOST RIDER #1 2ND PTG SPOILER VAR
JUSTICE LEAGUE DARK #1
JUSTICE LEAGUE DARK #1 VAR ED 
FLASH #51 VAR ED
THOR #1 2ND PTG WOLVERINE VAR
WEEKND PRESENTS STARBOY #1 2ND PTG NGUYEN VAR
X-23 #2
THOR #1 2ND PTG WARD VAR
AQUAMAN #38 VAR ED
MR AND MRS X #1
X-MEN GOLD #30 2ND PTG MARQUEZ VAR
AVENGERS #2 3RD PTG MCGUINNESS VAR
TEEN TITANS #20 VARIANT EDITION FEATURING CRUSH
AVENGERS #3 2ND PTG MEDINA VAR
AMAZING SPIDER-MAN #801 2ND PTG MARTIN VAR
I don’t understand how one issue can have two 2nd prints.