The starting point

Channel 4 hasn't mentioned the Euston manifesto yet, as far as I am aware. However, I found some favourable responses on their forum, here: Euston Manifesto: A path out of denial (esp. re 'the war'). Here is my response to one of the points raised:

jjb: The vast majority of that agenda would be supported by people of almost any mainstream political affiliation, right and left, so why is it claiming to be a new vision for left wing politics?

The manifesto says: 
'A. Preamble
We are democrats and progressives. We propose here a fresh political alignment. Many of us belong to the Left, but the principles that we set out are not exclusive. We reach out, rather, beyond the socialist Left towards egalitarian liberals and others of unambiguous democratic commitment.' (See also Section 11. A critical openness)

But the main focus is on reclaiming 'the Left' from those who think it begins and ends with opposing the war in Iraq, being anti-American and anti-Israeli. In general terms,  it is a fight against a climate of opinion in which people will believe any report, any interpretation of history, as long as it is anti-American, etc. People are right to say that the manifesto does not say much on bread-and-butter, economic issues; but, however corny it sounds, we must start by telling the truth, or trying to find out the truth.

As Norman Geras and Nick Cohen wrote in the New Statesman, 17th April 2006, 'our discussion focused on our common sense of discord with much current left-liberal thinking. We talked of how the prevailing consensus [the dominant anti-war discourse, etc]¨had ample representation in the liberal press, on the BBC and Channel 4, whereas the viewpoint of our own segment of the left was significantly under- represented in the mainstream media. We had, however, found a place on the internet and in the blogosphere...'

I would love it if we could spend more time seriously discussing the issues paulio mentions - 'demographics, peak oil and climate change'. Maybe, one day we can.