And don't include Peter if he's ultimately not going to be that focal or important a character in the actual story.
Isn't that basically what the Ultimate Spider-Man cartoon did with Wolf-Spider ?
For all we know Spencer has nothing to do with Spidergeddon, otherwise I think we would've seen teases to it in the ASM solicits when they're already doing a lead-up mini.
I wouldn't be surprised if it's another "event" mini, though it would be weird to do a Spider-Man event without ASM being a part of it (especially since then it would probably sell better).