Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
I don't think the 60GB will actually fit in a 40GB dock. I remember trying to get my friend's new iPod into my (40GB) dock.

Eww... That sounds gross, sorry. :(
 
As far as I know and from my experience an iPod will work in any dock it can fit in.

The problem being it fitting in the dock.

The iPod photo being the largest iPod, it would only fit in an dock made for it.

But you could fit any iPod (with dock connector) into the Photo Dock.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.