Ah ok I know what you mean.
However my intention was to create a "permanent" gallery .I mean, the users have their gallery that they can manage, come back later, check their pictures, add some new ones, delete and order them, kind of like myspace.
So it was quite annoying that they can see the others user's pictures and galleries.
The website I am designing use Wordpress Mu in a different way.There are thousands of blogs but nobody owe one.The main admin owe them all and the users are just author on all this blogs.It is a tabloid for the US High Schools, every school has is own tabloid and the kids post about the school they are logged in.
I made a lot of changes and added some functions and plugins to do so like a per-blog registration, friend plugin with add-friends buttons, private message in a lightbox, reward system with points for each comment post and post with picture etc and, the per user gallery management which works well on the original blog the users are logged in.
I am releasing it soon and I will post the link when it is done so you can see the result.
Now like I said my issue is to show the gallery and images from NextGen in the sitewidetags blog (Donncha's plugin).
I believe that I have to use the switch to Blog in a certain way but for now I have no clue.