Someone posted this link before but I found it very helpful is visualizing what Gus is up against (aka the wall I've referred to):
http://85.214.49.20/wz/pics/nws1.gif
The chart is kind of hard to read because its rotated but you can clearly see the ridge running thru Cuba and into the GOM. This high pressure bubble is currently protecting FL - Gus can't go thru it, he must go around. Right now he is kind of stuck and got ripped apart so the motion is very hard to judge. I assume this stalling motion has caused some of the models to show the track thru the Keys, but not sure. At this point it almost looks like the center is trying to reform off the western tip of Haiti, so it possible in the next update we could see a big jump indicating a western movement.

There are a couple of ways for Gus to reach S FL, but they all involved him moving much faster or much slower, neither of which are forecast. I personally think the NHC 5-day is too far west but the range of error at that time frame is so wide its anyones guess... thus I tend to just monitor the 3-day cone.