Once upon a time, I used the Diamond website (previewsworld.com) as the spine for my Comics Guide. Diamond listed seven publishers separately (BOOM, DC, Dark Horse, Dynamite, IDW, Image, Marvel) and all the other publishers under a lump heading ("Comics and Graphic Novels"). Books, magazines and toys were listed separately, as well.
As you can imagine, when DC went exclusive with Universal Distribution, Diamond stopped listing them. (Unless you had an account at Diamond where you bought comics from them, in which case you could see a list and order DC -- which Diamond would buy from Universal, presumably.) We were down to six separate listings, but still, everything could be found at Previews except DC. Universal doesn't really have a list that I've found, so I've been using a list from a sub-distributor, Lunar.
Now that, too, is about to change. Image has gone exclusive with Universal, so we can expect that listing to go away pretty soon. As for the remaining five separate listings, two of those have already gone away for other reasons.
What those reasons are, I cannot say. But Dark Horse and IDW are now lumped in with the other publishers in "Comics and Graphic Novels." When Image goes, that will leave just BOOM, Dynamite and Marvel (which shares distribution with Penguin Random House) as separates.
I expect BOOM and Dynamite pay for the privilege (possibly in the print product). Marvel probably does, too, but maybe not -- as the biggest draw, they might get special treatment. If payment is a factor, that might explain why DH and IDW have been downgraded.
But that's all speculation. Meanwhile, Lunar lists its other clientele as shipping earlier than Diamond does. (I usually go with Diamond, as they seem more accurate.) I don't know of any publishers who are specific to PRH, but there are some I never see, so that may be the case. Those I never see are tiny, so I just ignore them and rely on Diamond.
But for how long? Because this is the biggest news (well, for me, anyway):
Every Wednesday, Diamond has traditionally listed everything from the Big Seven (now the Big Four, soon to be the Big Three) two weeks early, and "Comics and Other Publishers" a week early. That is to say, this last Wednesday (May 31), I expected to get the full list for June 6, and a partial for June 14.
On May 31, I did get the full list -- the "Comics and Other Publishers" list (with DH and IDW) as it joined BOOM, Dynamite, Image and Marvel, which I had received on May 24. But as for June 14: Crickets. It's Friday, and not a peep on Previewsworld on what to expect after Wednesday, June 6.
This is awful for me on a personal level, because I can't get a head start on the Comics Guide I would normally post on June 9. But in a larger sense, what does it mean on Diamond's end? Without Image (and DC, and the bulk of Marvel), are they going to become a niche distributor? Without those big accounts, can they even survive? Does their reticence mean there are other shoes about to drop, in the sense of other publishers jumping ship to Universal or PRH?
I don't know, of course. But this abrupt change of course must mean something. And whatever it is, it doesn't bode well for Diamond.