Potlatch question - circled nodes?

What does it mean when I select a way and animated circles appear around most of the nodes? Did I hit a key I didn’t mean to?

Figured it out, I think - it means that there are two nodes on the same spot (was this feature just added?) These nodes aren’t duplicated, though, so I guess it’s a bit buggy. If I see it again I’ll probably report it on trac.

The feature was added just today I think.
http://lists.openstreetmap.org/pipermail/talk/2010-February/048048.html

OK, bug filed: http://trac.openstreetmap.org/ticket/2705