I've just upped my Guns skill to 100, but am still having 'sway' issues with all guns. I thought that having the Guns skill at 100 was supposed to completely eliminate the 'sway'. Is this not the case in New Vegas, or is it just another bug?

If you're strength isn't high enough for weapon you're using, the gun will be less accurate

This is true, though my strength is at 9, and the weapons I'm using are between 4 and 8 for strength requirement.

Weapons will always sway slightly, you'll get used to it eventually, try crouching

Well, if that's the case, they did change that aspect from Fallout 3 then. With Small Guns at 100 in F3, there was zero 'sway'. With Guns at 100 in FNV, there's still quite a bit of it, for me anyway. Even with the recommended strength requirement, as I previously mentioned.