Is the wrong Milibandwagon now rolling fast? That is Jenni Russell's concern in her Guardian column, making the case for her friend Ed over his brother David.
In the personality politics stakes, Ed Miliband had probably the best week of any frontbencher in Brighton, and has impressed many in the party in the run-up to Copenhagen. But Westminster wisdom sees him as the main loser from his brother's decision to turn down the role of EU foreign minister last week, which has been taken as surely confirming that David Miliband intends to be a candidate whenever Labour is next electing a party leader.
If Ed Miliband would be close to joint favourite, and among the leading two or three candidates 'with a run', but his brother's candidacy near the head of the field too would appear to present a significant roadblock to his own prospects.
Firstly, both Miliband brothers have handled any sense of an emerging rivalry admirably. They could be cast as the Blair and Brown of their generation, having been key policy advisors to the 1990s principals, but comradely fratricide seems an unlikely outcome. (However, among the ex-Brown proteges, Miliband E may even be doubly squeezed by a two Eds as well as a two Milibands dilemma).
Secondly, this all remains very premature. In the event that Labour were to be defeated at the General Election, it would be very well advised to wait until after the Autumn conference before beginning a leadership contest, as the Conservatives did in 2005. No potential future leadership candidate has really yet offered a pencil sketch of the contours of a substantive future agenda. And the party will certainly want and expect candidates to focus all of their efforts on the General Election in the next six months.
Thirdly, when the time comes, the party should indeed want a fraternal and open debate where it can choose between all of the leading contenders.
For now, the future leadership stakes should certainly include both Miliband brothers, along with Yvette Cooper and her husband Ed Balls too.
Considerably more implausibly, Next Left suggests that perhaps they should all remain in the field for the contest itself too.