Here's The Independent's preview.
In today's speech, Ed Miliband will argue: "We lost that radical edge. When it came to the bankers, we let being in government constrain our willingness to be as radical again. Let's be honest, Gordon's response to the financial crisis was incredibly bold and helped keep the economy afloat.
"But our response on the excesses of the banks – and the role of the nationalised banks – has not been all it could be. We should have done more to take the opportunity to rethink the banking system and to show our determination to tackle what had gone wrong."
He will pay tribute to Mr Brown and refuse to blame him for Labour's election defeat. Referring to the former prime minister's criticism of a 66-year-old "bigoted woman", he will say: "Let's not try and explain away our defeat on the basis of one person or one moment in a campaign."
Ed Miliband will tell the conference: "We must start by understanding the country we seek to lead again and the reasons why we lost. I will always defend the fact that we made this country more prosperous, fairer, more democratic ... But there is deep thinking we need to do about what went wrong.
"For me there are two central lessons: we lost touch with the lives of the people we represent; we lost touch with the progressive ideals that characterised the earlier years of the government."
The Guardian rounds up the speech and other leadership developments.