itunes home sharing

[jcott]

I have had itunes on my pc for several years. I just recently purchased my first mac. I turned Home Sharing on my pc first and then my new mac. When I turned home sharing on my mac it said this was my third computer registered. I do not have any other computers. I do have four different iOS devices, could it be counting one of them if I have downloaded something directly to one of them (I have downloaded aps directly to an iphone)? Is there any way to verify what computers are authorized for Home Sharing to a particular itunes account?