Version:           2.0-SVN (using KDE 4.1.2)
OS:                Linux
Installed from:    Fedora RPMs

When you click on a single album name or a stream collection it will select all files associated with that particular album or stream. This seems to be working alright.

Although when you try to select multiple albums at once, using the CTRL key on the keyboard, and clicking on a top-level item, it will not select all files associated to that item which results in leaving items unmarked. I think the expected behavior should be that all items associated with the top-level item should be selected.