I've had two players recently call me out, as I have them on my enemy list.  How is it that they know they are on my enemy list?  I thought that was private.

If they are standard, then tried joining a game that you were in, and were blocked, then, they could make an educated guess.

So they can't join any game that I am in, or only the games that I initiate?

i believe it's any game that you've entered first. 

EDIT:
according to help/wiki:
"Your enemies cannot post on your profile wall and you can use your preferences to set whether they can send you Private Messages. Also enemies with standard accounts cannot join games that you have started or have already joined. " 

Yes, all except tournament games.

I thought that an enemy could not even see a game you created, is that true?  I see that it does not say that in the help section, but I thought I remembered that.

SquintGnome wrote:

I thought that an enemy could not even see a game you created, is that true?  I see that it does not say that in the help section, but I thought I remembered that.

No.  I tried to join one last week and it told me I could not because I was listed as an enemy of one of the players already joined.  But it was available on the "join game" list.

Did it say which player? or just that you couldn't?

It did not say which player.

However there were only two joined in this particular game and I found a different game with one player and was able to join it.

This is really helpful, thanks.

Nice avatar BTW.

SquintGnome wrote:

I thought that an enemy could not even see a game you created, is that true?  I see that it does not say that in the help section, but I thought I remembered that.

I think that this was a suggestion or request someone had - I remember reading about this too.