When I enable X-Axis Mirror under Armature Options in edit mode, then use Shift+E to Fork Extrude a bone. The bone I am dragging goes where I would expect, but the forked version goes in a really weird direction, not even same scale. Here is a picture that hopefully shows up (my first post here):
Sorry, for some reason the ENTER key isn’t working when I type this. I’ll try to fix the formatting if I can edit after I post this. I’m using Blender 2.66.1. Working in Edit Mode, have tried different Pivot Center options. I checked that my model doesn’t have any weird rotations by pressing G then X and dragging, then X again (to switch to local mode) and dragging more… the x-axis is correct. I also tried CTRL+A and Apply Rotation and Scale to make sure nothing was pending – no change. Possibly related issue. When I drag any object in Object mode, it moves all objects in the model (not all by the same amount), I don’t think my other models usually work that way, but I have been away from Blender for about 6 months, so not positive (it is annoying though, have to switch to edit mode just to move a single object).
You have problems with the X Mirror because the origin of the armature is off center. That’s the orange thingy that you can see above the hand of your character on the screenshot. Blender uses it as center for the mirror.
To fix it, select the center bone (the vertical one) or just its head and press [SHIFT S] --> “Cursor to Selected”. Then [TAB] to go back to Object mode. In the Tools shelf on the left (Shortcut: [T]), search for the button “Origin”. Click it and select “Origin to 3D Cursor”. That will fix your mirror problem.
While you’re still in Object mode, press [O] to disable the proportional editing. That will fix the “problem” of the objects moving all together.
Since you said that you moved all your objects in Edit mode because of the proportional editing, I strongly suggest to fix all their origins. Moving the origin must be reserved for special cases, when you need it and know what you’re doing. 
Thanks a ton! I did move the origin for all objects I think, because I was trying to fix what I thought was an origin issue when importing my model in to Unity3D. Turns out that was a non-issue, but now I get to fix all the origins, hehe. Thanks again!