[ALUG] Moving from Xubuntu 9.10 to 10.04, sharpness seems to be worse

I have just upgraded my system from Xubuntu 9.10 to Xubuntu 10.04, it seems to me that the sharpness seems to have subtly deteriorated. I have checked some of the obvious things (like the screen resolution hasn't been changed). It was most immediately noticeable in my terminal windows but, on looking carefully, I think the effect is general, it's just that I use smaller font sizes in my terminals than elsewhere. Has anyone any ideas what I should maybe be checking to see what might have caused this? It could of course be that I'm getting older and my eyesight is failing! :-) -- Chris Green