I read the white paper on Rootstock:
http://www.rootstock.io/#white-paperI think it has a good chance of succeeding. It has a key dev on their term via Sergio Lerner and now is getting large funding from the likes of the Digital Currency Group (ie. Barry Silbert):
http://www.coindesk.com/smart-contract-1-million-bitcoin-rootstock/It's a game changer for bitcoin. It's solves scalability, enables micro-transactions, gives it turing-complete capabilities, etc. It would threaten Ethereum because there's no need to go through their network.
So why would anyone then use Bitshares? Just create a sidechain based on Rootstock, fork Bitshares and wham! You just instantly created a bitcoin trading platform that can do 100k txn/sec and has all the other great BTS features.
The only way to head this off is to get a bitcoin sidechain working for bitshares before Rootstock takes hold. Bitshares has zero network effect right now, so a migration to a copied bitshares w/ bitcoin security wouldn't be hard to imagine.
I know bytemaster believes bitshares should let others get sidechains going, but it would be a mistake if there's no immediate plan for someone to do so. We've all discussed the positive game-changing effect a bitcoin sidechain would have on bitshares. But there's now a threat that I think makes it imperative.