Doug -- I think you hit the nail on the head with most of your analysis, though I wouldn't go for the Charley scenario at all right now. Dennis is probably a strong enough storm -- and will be one -- to be able to resist much of a sudden turn to the northeast. It is already strong enough to appear to be eating into the southern extent of the ridge, likely a result of weakening steering currents in the region as the pattern tries to change and the hurricane enters the area. What it all means...well, we'll just have to wait and see.

For what it's worth, the 12z GFS takes the storm almost north from here, bringing it very near Ft. Myers, then turning it back to the NW. Landfall ultimately occurs in ~54hr near Destin after riding up the coast from Apalachicola. It does slow it down west of Tampa, which would be interesting to see if it occurs, just for the final impact it'd have on the track.