Do the photos in photo stream take up disk space on my ipad2 and my iPhone??
Yes because they are actually physically on your phone/pad (even though they are also on the cloud). But pictures in the photo stream aren't counted in the space used on iCloud.
Thanks for the answer? So, is it possible to delete from photo stream???
You can only delete the entire photo stream. Here is how http://support.apple.com/kb/HT4890
Let's hope that apple will bring an option to delete a particular picture from the stream...
You can actually delete individual photos from within iPhoto. Just found that out today as there was an update to allow this.
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