the Viking still flies with a crew of three in most overseas AOR's. There will only be 2 onboard if it is only a dedicated tanking hop like Yo-Yo tanking. Otherwise there will always be a second NFO onboard as the primary system operator for the secondary mission.
The Viking can carry up to 10 MK-82's, but you would have to take the buddy store & right drop tank off which will rarely happen on deployment. More often these days you'll have a couple of Mk-82's in the bomb bay and the normal tanking external load, or if on a specific mission a SLAM-ER or Maverick missile on the wings.
That being said, there are 2 NFO's in an S-3 and 1 in a Super Hornet. So there will not be an opportunity for all NFO's to go to that community. They are going to Prowlers, E-2's, P-3's, EP-3's, E-6's also. Every community is taking a "fair share" of the S-3 guys. The sundown of the S-3's seems to always be changing but the last squadron will close their doors in 2008 (maybe 2007 w/new budget). It is always changing based on the TSPAT though.
As for the F/A-18F mission, others can answer better than I can, but I would expect it to be the normal air to ground and air to air missions that the Tomcat and Hornet fly today. The F will just have a different capability in filling those roles.