when i enter events on iCal on my desktop (iMac), those events do not get pushed to my other devices; but if i enter events on iCal on my iPhone or iPad, those events get pushed to iCal on my desktop. iCloud is set up and appears to be working in every other way.
You are entering the events in the wrong calendar on your iMac, select the iCloud calendar (in iCal) and use it.
This does not necessarily have to be the case. I have the same problem, and I am using the correct calendar.
I am also experiencing that ical does not send out invitation emails to other participants in events anymore. I haven't really changed anything, it just stopped working.
Has anyone discovered a solution yet?