Earlier today I went to LEGO.com on a whim to check out the Collectible Minifigures. I was surprised to find that the five figure limit had been lifted from Shop at Home (US)! It didn't last long though, as they are currently sold out.
I don't know what the occasion happened to be, but according to the client service representative they lifted the limits this morning.
Check LEGO.com in your region in the coming days, as they may be lifting the restrictions there soon!