I was uploading a photo at http://www.pigduck.com and at first the photo was too too and it moved my sidebar downwards.
So I resized the photo several times and suddenly my font below that picture has changed to italics. I'm not sure why.
I re-uploaded the Yadda theme but the italics font doesn't go away.
When I change it back to the default WordPress 1.5 theme, it's still italics.