Are you wanting to use either the iMac or the Macbook Pro as an external display or do you have an additional display for your two macs? At any rate, using multiple displays is fairly easy in 10.9. There are, as you may have noticed from some of the comments here, a few little inconsistencies, but nothing major and nothing that Apple doesn't already know about.
There's no way I can think of to do a direct wireless display connection between the two. You would be able to use screen sharing, maybe, but that's slow and not really what you're looking for.