Yesterday PCalc developer James Thomson heard that he'd have to remove the calculator widget from his app. There as some concern, apparently, that calculators were too heavy for the Today view extension system. Today, iMore has heard that the situation has been re-evaluated and that Apple will now allow calculators as Today view widgets.
I speculated last night that calculators as widgets might not have been something Apple expected, and that the situation might have resulted in a lot of discussion within the company. If that was indeed the case, then it's equally likely that the discussion got escalated, and was ultimately decided in their favor.