Yes you can use it out of the box. The Traktor edition delivered with the DDJ-T1 is a limited edition, meaning it only has limited functionality.
No it is not possible to control sample/remix decks on the T1. The F1 is a good alternative.
Pioneer does not condone 'gossip' within their forums. So no one here can give you an answer to your last question. However, it would surprise me if there is not a DDJ-TX in the making. Can't confirm it though. It comes when it comes :)