Hello friends! I'm traveling on business right now and I may not be able to check these boards often but I will try.
Boxing vs Fencing footwork:
The one thing that I've noticed with fencing footwork is the emphasis on full extension. Which makes sense in this case since you wish to have a full range of distance to land your point on the target.
in fencing the feet are perpendicular to each other where as in boxing your feet tend to parallel, with the hips squared. Again the idea of extension comes into play, in boxing you want to have TWO weapons equa-distant to your target and have the ability to use the same amount of force from either weapon. In fencing the feet are parallel and your hips are not square to your opponent, they are side ways. This gives you more range with your single weapon.
movement comes in in major categories, linear and circular. linear movement is very similar to boxing. your lead foot comes off of the ground slightly toe first then heel with the heel ending up where the toe wass positioned before. when combining with a strike, the weapon moves first just before the advance is made. Circular movment is also similar (but much more similar to stances that have power-side forward). Rear foot leads movements and the lead foot follows.
Circular movements then lead into attacking angles, which is also done in many other martial arts. Here is an example of The Spanish Circle taken from classicalfencing.com:

Diestros A and B stand at opposite ends of the diameter. To insure a safe position Diestro B responds by moving and maintaining the diameter. Red line is the new diameter.

Diestro A stops at point C while Diestro B continues moving, thus creating the opening for Diestro A to attack at an angle. Diestro A steps in at an acute angle along chord CD. Red lines indicate the acute angle.

Diestro A's rapier travels at an even more acute angle toward Diestro B. A's rapier controls B's blade by opposition as it travels forward to B's face.

Diestro B raises his guard (hilt) and deviates the point of Diestro A's rapier (desvio). At the same instant B steps slightly to his right and lowers his point toward Diestro A's face. Diestro A impales himself by the force of his own attack.
To execute an efficient Desvio the Diestro must place his blade against his adversary's blade in such a manner as to not only deflect the attack but to enable him to counter attack in the same movement. This can only be done correctly if the Diestro has an understanding of angles and the different mechanical advantages achieved by the placement of his blade on the adversary's blade.
Again, i encourage people to read more about fencing to find the concepts in them and see if they can be applied to your own martial training. Had i the time to do so I would gladly take fencing lessons to help gain further insight of my own physical attributes.