Speaking purely from educated speculation, it seems clear that Carr is keen to be the next Labor Prime Minister. Carr is 58 this year, so still has plenty of good years ahead of him. He has a national profile, a high approval rating, and plenty of achievements under his political belt. Carr would be an ideal member of the Federal Labor team, clearing away some of the dead wood and injecting some ideas and passion into an otherwise moribund front bench.
Consider the timing: the next Federal election is a little over two years away, and Labor preselections will take place early next year. There are a fair few possible vacancies in seats nearby to his cushy Maroubra electorate. In Banks, Daryl Melham has probably had his day, whilst in Blaxland Michael Hatton has done little since replacing Keating in 1996. Both would surely face tremendous pressure to move aside for Carr.
For Carr, this is not the end, just the end of the beginning. Give him six months enjoying the Bondi surf and then he'll be back hungrier than ever.
Watch this space.
Bob Carr and The Wiggles - another possible career move?
UPDATE, 1/8, 11:50am: A few people have posted comments correctly explaining that Carr's personal approval rating amongst NSW voters is very low. They are absolutely correct, but miss the point that if he is to be a federal minister, his national approval figures are the one's the matter (provided he can find a safe-ish seat in his home state). Although it's unlikely that national approval ratings are tested for state Premiers, I suspect that he would rate very highly, particularly amongst Victorians, WA and SA voters who see him compare favourably with their own Premiers. Also, these voters are spared the drudgery of travelling on Sydney trains and experiencing the crime of Sydney streets, two of the factors which are supposedly hurting Carr locally. Though he might be tarnished slightly in his home state, this is far from irredeemable, and he is well liked and respected nationally. Bat on, Bob.