Ah, now I get it!  

You were right, there is indeed still a main site (I guess I was thinking of the deprecated is_main_blog. Or something.  Anyway I wasn’t getting it!)

My problem was that on my main site, I did not have SP activated.  (The main site is sort of a gateway, which doesn’t do much itself, and doesn’t need a forum).  So I tried activating SP on the main site, and that took care of everything.

Now, the SP updates appear on the /wp-admin/network/update-core.php page as they should, and updates there work fine.  They even appear (and work) if I’m coming to the network/update-core.php from one of the other sites, not the main site (which wasn’t working before).

So I guess we can mark this one solved, and just remember that the answer is that you have to have SP activated on the main site, even if you’re not going to really use it there (just activate and then delete the forum page, for example).

Thanks so much for all the work tracking this down.  What a relief!

well, thats interesting… hadnt really thought about main site not having it enabled…  makes sense now that you say it…  but to see updates there, would need to be enabled…  when we do our tighter integration with multisite soon, will have to see if some other way to deal with that…

I came here to report the same problem! We only have Simple:Press activated on one blog (not the main one) in our multisite (3.3.1) install. The update is showing on the individual blog’s plugin page but not anywhere else.

I will try activating it on the main blog and see how I go.

Alright… That seemed to do the trick. I liked that I could also update the plugins and themes from that page too. One anomaly I found was that after I updated Simple:Press it still thought there was an upgrade on my forum blog. Once I told it to upgrade again it was fine.

yup.  only the super admins can upgrade the plugin… dont really want lower network sites changing files on your server do you?

you can either do a network upgrade on simple press (as super admin) or each network site individually…