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Yes, but you can log in with your regular Steemit username and keys, so no need to sign up again.

I'm paranoid about giving any site besides steemit my login credentials.

That's good! But there are some keys that are okay to give away, while others are not so okay. It all depends on what you are comfortable with. I personally have no problems with giving away my posting keys to websites I trust, but others might not. You should never give it away if you are not comfortable with it, but then your only option is to collect enough Steem Power to get it to unlock here on Steemit ;)

After I figure out image posting I might look into keys. lol Is there a like key?

Hehe, there's a lot to learn here!

No, there is no like/voting key, but there is a posting key that will allow the user to upvote, flag, comment and post with the key, but not transfer anything.

Hmm. So can I borrow yours? ;) lol jk