Is that true that we have to move all our coins to a bitcoin core wallet so that in case of a fork to Bitcoin ulimited we have our coins also there? I heard that it is not good to leave the BTC at exchanges because they won't deposit these BTU 1:1 to BTC. Anyone knows more?
No we don't have to move our bitcoin core to BTU it will be automatically doubled / replicated. And besides that is still on debate and this is just politics. As of now, there's no real deal on this BTU however there are a lot of people that wants to migrate on this "rogercoin" but you don't have to worry about it.