According to finnish F1-site, which was worlds first to break news that Kimi would have a deal with Ferrari already on 1st of August, is now saying that unlike usually Kimi & Ferrari's deal was never about the money - they agreed on that very early on. The little details, mainly about outside the actual racing part, were the ones they had to fight for according to their source.
Apparently also, in the contract, they've agreed that it's up to Kimi when they'll release news on the contract, but Ferrari gets to decide how they do it (Big press? Just notification on website? Whatever else they want?). Also Kimi slipped in an clause saying that he doesn't have to be there when it's released.
All this of course is assuming that their source is right and that the deal actually exists.