The only thing that worries me is that these preview images are just showing us regular clockworks blocks with a new skin. Hopefully they are just showing the first level of the mission and the other level has more exciting stuff to come. I guess we'll see soon enough.
These are linked from the Spiral Knights Twitter page.
There's a 3rd screenshot posted earlier this morning. I figured I'd link the others so you don't have to go hunting around this thread for screenshot #2.
Screenshot #1
Screenshot #2
Screenshot #3
Click to enlarge, these are more clear than the fb photos! (e.g., poison effect on screenshot #2)