According to the latest news from SUMO official thread:
Exchange UpdateFYI,
Livecoin.net has accepted our submission. SUMOKOIN will be listed there within 20 working days if no technical issues arise.
Livecoin is one of a few decent exchanges that can list Cryptonote-based coins and they have quite good volume for XMR. We think it's the best choice for us atm to avoid depending on single exchange.
SUMO Fairpool hashrate is on the rise too.

Don't miss the party, it is not too late yet.