why isn't my photo stream not syncing

So, you've signed in to icloud (settings-icloud) on all the devices with a VALID icloud account? And you've turned on photostream (settings-icloud-photostream-set to on), on all devices?

According to http://www.apple.com/support/systemstatus/ all icloud services are up, and there have been no reported issues for several days.

So you have been able to use photostream across your devices in the past, and this issue just started?

Try resetting your devices, hold home/sleep buttons until the device powers off then powers back on and you see the apple logo, once the logo appears release the buttons, then try syncing again.

When you say "test file" what you do mean? you're saving something to your camera roll and expecting it to transfer? Have you tried taking a new photo and see if that will sync?

So you're able to use the internet on your devices, you have verified photostream is on. I am not sure what else there is to check.

The only thing I can think of is to try another iCloud sync feature, try updating a note and see if it syncs.

In order to have pictures sync to Photostream, you must be on Wifi AND exit the camera app. You said above that you are using Wi-Fi already, so good there. Try shutting down the camera app while you are on Wi-Fi and see if the sync works.

Did you ever figure out what happened? It's happening to both my sister and I now! VERY frustrating!

When you take a new photo on your device, then close the Camera app and while connected to wifi with at least 20% battery life remaining on your device, see if the photo appears in your My Photo Stream album after a few minutes. Do this on any devices you are having trouble with and let me know what you find out and I'll try to help you.