Installed Xubuntu 8.04 Beta (not sure which version of the beta) and just like the final release of Xubuntu 7.10 I get a "big font" on the login screen. I have a PCI legacy ATI Radeon 9250 graphics card.

I managed to find a fix for the "big font" problem by editing xorg.conf and inserting these lines into the section "Device" :-

Option "UseEdidDpi" "FALSE"
Option "DPI" "96x96"
Option "NoDDC"

This also fixed the same "big font" problem on the beta of Xubuntu 8.04. Just thought I would add my two cents for what it's worth. I have filed a bug report on it anyhow. Maybe newbies won't be scared off by seeing such a disfigured login screen.