Good stuff from Iain Martin:
[Ed Miliband will] have to deal with Ed Balls and Yvette Cooper. Balls is an impressively robust “big beast” who wants to be shadow Chancellor, but Ed Miliband may not fancy sub-contracting his economic policy to someone so tricky to control. Subverting Lyndon Johnson’s famous rule, keeping Ed Balls inside the tent makes no difference - he’ll probably still urinate on his colleagues.
On the other hand, the Treasury brief is even more important in this parliament than is customarily the case. So if not Balls, who? the trouble with appointing Yvette Cooper is that, no matter how capable she is, she's still Mrs Balls and, more to the point, putting her at the Treasury risks being seen as a slightly too transparent attempt to control Mr Balls.
So perhaps Ed needs a compromise candidate. Happily there is one: Jim Murphy. The former Secretary of State for Scotland deserves a more prominent role than he has so far enjoyed. I'd initially thought he might be an obvious candidate to shadow Liam Fox at Defence but perhaps he could rise higher still.
Murphy, lean and hungry of look, is an adept, unflappable media performer who also, actually, has more opposition experience than the rest of the Labour party: he's performed well against Alex Salmond. Just as importantly, Balls's style is such that invites the response Well, he would say that wouldn't he? Murphy, more reasonable, more low-key, but just as forensic might actually receive a better hearing and prove more effective.
If I were Miliband I'd give serious consideration to making Murphy Shadow Chancellor while asking Balls to be Shadow Home Secretary and Cooper to take on either Health or Defence.
UPDATE: Not that Miliband will take my advice (foolish man!). As Pete notes, Murphy doesn't seem to be listed in the runners and riders.