I guess most of you have allready seen the image Scott Allie linked and removed on Twitter today already, but I took it appart for a discussion and thought I might as well post my findings here too.
The original image (enlarge to see properly):
Yay, Spike is going to be in the upcoming comics, I'm guessing #34 or #35, considering that the pages are completely ready to got to print.
I do also think the image could be a flashback and is one that involves a series of images, putting together some mystical events.
This picture here is (as
2maggie2 pointed out from issue #31, where Willow is zapped with energy from an event in the future.
My theory would be that this magic conundrum is linked to the slayer spell somehow and that back then Spike might have been affected too, playing mystical conduit and all.
I think the Elisabeth taylor amulet might be visible here, but the image is too blurry to tell.
Anyway, even if it's just a flshaback it seems to be a sure sign that he's going to show up very soon (or has already shown up by the point this page comes into play), so yay. For better or for worse something is moving forward and Spike makes everything better, even S8.