(I typed an answer to this, then got nervous that I'm telling the internet when the house will be unoccupied)
Answer: the end of June. We'll be back in plenty of time for Stephan to go to work on July 4th. We're getting really excited about it. Stephan got his last vaccines, and we have the malaria medicine and just-in-case stomach medicine. We haven't started packing yet though. Packing is going to be a bit different this time- the goal is to pack minimum personal items (cloths, etc.) and leave plenty of room for the medicines and medical supplies. Everything gets measured and weighed so we can distribute it evenly across everyone's luggage.
In case you haven't seen it yet, check out the Global Medical Brigades website, some photos from their recent trips, information about the 2008 Medical Brigades, or the local organizations that we're going to work with, click on the links.