Sorry, this is an example of why Vulcans don't tell jokes....

The GFS minors out the circulation as it drifts it southward offshore.
The ETA emerges Ivan off of the Mid-Atlantic coast and actually re-organizes it as it moves south, then southwest.
The reason the model shows for doing this, is that now both models are strengthening a trof in the N.E. U.S.
IF the ETA's scenario is correct, what would likely happen is Jeanne would have to move around it. I believe Clarke gave that scenario earlier. The ETA actually has both systems interact, but the problem is, it loses Jeanne, and its reflection of it is probably not accurate.
Here is a link that loops the images so you can see the progression.

http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/eta/12/index_slp_m_loop.shtml
At this point, it is my opinion that the remnants of Ivan are at least likely to move off of the coast, since this has been the trend. What happens after that is unknown.