I'm using the OSS radeon drivers and no, fortunately it was fine after a reboot :)
Corrupted memory was my first thought, but affecting only text is odd - I mean, the drivers aren't even supposed to know those particular pixels are text, right?
Not necessarily, no, I think graphic cards are aware that certain things are text. For example, I have a thinkpad t400 with two graphic cards(ATI and intel), on the ATI the text in consoles is not anti-aliased, but on the intel one it is. So I'm pretty sure that the graphic card(or at least the drivers) are aware of what is text and what is not to some extent
