I am having the same issue. Photostream was working fine on my iPad3 until today. First, no new photos were showing that were taken on iPhone, but they did show in iPhoto on MacBook Pro. I tried turning photostream off and then on and then restarting iPad but now Photostream on iPad is completely empty. Any ideas how to get it working again?
Same issue. New iPad (Verizon 4G) Black 32GB. Photos syncing across iPhone and iPad fine until late today (approx 4pm EDT).
Took about 10 photos after 5pm this evening and they are not syncing. Finally I lost all pictures in photostream on the iPad (still present on iPhone). I deleted the iCloud account from the iPad and re-added it.
Turned photostream off and on, restarted iPad.
Finally photostream populated all of the photos that were present before 5pm, but it is STILL NOT syncing any photos taken after 5pm today.
Well, in my case, the photostream did start working, insofar that any 'new' photos I take are populating into the photostream. However, the ten photos that did not transfer into the photostream yesterday, which I took between 5pm and 6pm, have still NOT transferred into the photostream. Since several new photos, taken after those 10 photos, have transferred to the photostream, I've given up hope that those ten will transfer.
Now I have to manually hook up the iPad to my macbook to transfer those photos as they are pictures of my three children and two of their cousins that I captured during a birthday party for my youngest (he turned four yesterday).
A friend mentioned that he once experienced photos not transferring where he had taken several photos in very quick succession. Indeed, that's similar to my situation (all ten photos were taken in under a minute).
Glad it's working for all of you now.