They just launched a twitter handle for the exchange today along with the news that community voting to add 5 coins for free is starting in a few days.
https://medium.com/@txbit/txbit-io-community-coin-vote-round-1-ca1b23b35f87
It looks like the exchange will be going live, at least in some beta form, once the voting ends.
Well, hopefully a developer will answer in detail, but I know that Solaris Masternode owners will be able to get a % of the trading fees from the exchange. I think they plan to have a staking option at some point too but don't quote me on that part just yet.
As far as Kucoin Shares go they can't be mined (as far as I am aware) so Solaris is a bit different since it's still being mined (through POS) and has Masternode rewards from each block too.
Here's the article that gives the most information at this point.
https://medium.com/@solarisXLR/txbit-io-dev-update-03-solaris-rewards-benefits-and-a-look-inside-the-foundation-ac0c02004451