Ubuntu :: Why Does Root Own All Files

I was trying to extract a tar file to my home directory. The operation failed because I didn't have permission! I did an ls -Al and discovered that all my folders and files are owned by root, and the group is plugdev.

I am a member of the plugdev group, and (ducking for cover) a member of the root group. Nevertheless, I seem not to have the necessary permissions on various folders and groups. I even went so far as to sudo chown individual files, directories, and directory trees. Using the -v switch, chown reports changing all the files. But, entering ls -Al, shows nothing was actually changed. I don't see in the new release notes that this is a new behaviour. On the other hand, I often miss the obvious.