The first seven burn posts are on track to earn 'stated' rewards of about $600 each, which breaks down into 50% SP (about 72 SP at a current price of 4.12 USD) and 50% SBD (about 300 SBD at a current price of 6.57 USD) for a total value of roughly 2270 USD per day. At a STEEM price of 4.12 USD this equates to about 550 STEEM per day burned, with 478 STEEM of that purchased from market, along with 300 SBD per day (currently worth 1975 USD) sold to the market.
The actual experience in the first two days, which have now been paid out, bought and burned, is slightly different from this due to actual market prices, and can be seen in the "proof of burn" replies on each post.
I consider this as a mild success, at least in terms of a proof of concept. In terms of direct economic effect this is clearly limited, although when selling the SBD to buy STEEM, a modest reduction in the SBD price is clearly visible in the price chart. If stakeholders continue to support or increase support for the initiative then it can have a greater impact, at least cumulatively over time.
Going forward the posts will shift to a new dedicated account @burnpost (click follow now!) with slightly different rules:
SP: powered down at the maximum rate to @null if SBD is at or below 1 USD, otherwise left in the account.
STEEM: sent to @null if SBD is at or below 1 USD, otherwise powered up and treated as SP above.
SBD: sent to @null if SBD is trading at or below 1 USD. Otherwise, traded on internal market for STEEM, which is powered up and treated as SP above.
In no case will any coins from the account ever be sold, transferred, or powered down except to @null. Any value in the account can be considered as irrevocably allocated for burning either immediately or a some time in the future.
Voting: The account will be non-voting. I haven't decided whether the account will delegate its SP, but if so my current intent is to delegate to some downvote-only objective anti-abuse initiative (such as being used to downvote mass spamming).
EDIT: Rewards from this post will be sent to the new @burnpost account and handled according to the above rules. (Other donations sent to that account will be handled likewise.)