Found this info on the Nora Roberts web site
"Divided in Death, a February 2004 release, begins a new chapter for J.D. Robb. The 18th book in the series is a hardcover and all upcoming originals will be published in that format. Before the move to hardcover, Nora came to an agreement with her publisher that the paperback reissues of hardcover IN DEATHS would be released six months, rather than the traditional year, after the initial hard cover run."
looks like she is re-releasing all the in death in Hard Cover so be careful when you buy it wasn't one you already read
Here is the release schedule
January: KEY OF VALOR/Jove
February: CHESAPEAKE BLUE/Jove Reprint
*DIVIDED IN DEATH, w/a JD ROBB, G.P. Putnam's Sons* new
March: NAKED IN DEATH, w/a JD ROBB, Putnam reissue
April: BIRTHRIGHT, Jove Reprint
May: REMEMBER WHEN/Berkley Reprint
June: A LITTLE FATE/Berkley Collection
July: HIDDEN RICHES/Berkley reissue
August: DIVINE EVIL/Bantam reissue
*VISIONS IN DEATH, w/a JD ROBB, G. P. Putnam's Sons* - New
A LITTLE MAGIC/Berkley reissue
September: DIVIDED IN DEATH/Berkley reissue
October: GLORY IN DEATH/ Berkley reprint
NORTHERN LIGHTS/G.P. Putnam's Sons
ONCE UPON A MOON/ Berkley Anthology
December: BLUE DAHLIA/Jove