How will the photo stream work?

[tl01]

Will an actual copy of my photos or videos stay on my phone after I take them or will they just be part of the stream? Once they are part of photo stream, will a copy also be kept as a back up in the Cloud? Will I be able to update all my previous photos in iPhoto to iCloud?
Thanks!

 

[androiphone]

read this http://www.apple.com/icloud/features/photo-stream.html

it only stores the last 1000 photos you took or for the last 30 days after you took the photo (whichever comes first), so you will still need to keep a full local copy on your computer, but if you want some photos in iPhoto now on your phone you can add them to photo stream so they can be viewed on an iphone ect.