Currently Being ModeratedDec 7, 2012 2:59 AM (in response to nikpayn)
I have the same issue. I have an iMac, a Macbook, three Apple TVs, two iPads and four iPhones in the house, Up until upgrading to iTunes 11 streaming worked just fine. This is just awful, as I have thrown out my CDs and if home sharing now doesn't work properly, I have to go back to plugging in iPod Classics around the house to play music.
When I start a movie, if home sharing works at all, it often drops out and then shows the Apple logo in My Computers instead of my library. Looking at my iMac, it is not sleeping. It even happens when I set Caffeine to stay awake indefinitely.Sometimes sharing won't work at all, sometimes only for a few minutes.
I hope Apple's upcoming patch fixes this. You'd think this would have come out in testing in-house.