anaconda doesn't seem to refresh its main window during some of the longer-running operations. I was dragging around the override-redirect popup thats coming up during the "Post-install filesystem changes", and the main window did not redraw at all. Again, probably not a big problem in the traditional installer use case, but not an acceptable experience when using anaconda on the desktop to install to disk.
Should be improved in CVS. There could still be some lag, but the amount will be greatly reduced.