I've been putting up with this for probably too long. For some odd reason, when I used the Photoshop CS5 eyedropper tool, it sets the background colour - which is really annoying. I've never experienced this in all my years of using Photoshop. Each time I set a colour, I'm forced to then use the x keyboard shortcut to swap the background/foreground colours.
How do you get the eyedropper tool back to the default setting? (without re-installing :)
Wow - ok it was easy. Go to Window > Color, then ensure the foreground colour is the selected one. There's a really fine, almost un-noticable line around the one that is selected. Mine was set on the background colour.