See this screenshot of a pre-instaled F17 vm where I run the netinst.iso for install.
https://docs.google.com/open?id=0BwoPbcrMv8mvR3RkdGhwd3JYaDA
It is not so clear in my opinion (at list it took half a minute to me to understand... forgive me ;-) to click on right most column of each line and see a drop down list with "preserve, reclaim, delete".
What do you think?
It could be better to put an arrow or to explain better in the text placed before the window