Shortly before Pope Benedict’s 2010 visit to the UK, L’Osservatore Romano (15 Sep) published an interesting short essay by Tony Blair on "The Pope and Newman". The present Pope, Blair says, is "much in tune with the spirit and ideas in Newman’s writings." The former prime minister asks those ideas are still relevant, for "elegantly written and subtle theology does not make you a public figure or get you into the headlines in 2010."
Famously, Newman ranked spiritual truth above all other values. "A man of conscience is one who never acquires tolerance, well being, success, public standing and approval on the part of prevailing opinion, at the expense of truth" he wrote.
What I learn from Blair’s article, is that

Newman was first to put the concept of development on the map. His understanding of how doctrine developed proved extraordinarily influential in his time. He made development a key idea both inside and outside the Church. We probably would not be using the terms "Millennium Development Goals" or "international development" today if he had not first used the word in his theology.
For the life of the Church today, Newman’s reflections on the development of ideas evidently have no less profound implications. He concluded it was impossible to fix a point at which the growth of doctrine in the Church ceased. By implication it is still going on today, and not in a vacuum. "The idea never was that throve and lasted, yet like mathematical truth, incorporated nothing from external sources", he wrote.

The possibility of new ideas and practices, of "development", challenges much of the church today, not least its Anglican component.
Writing particularly from a Roman Catholic perspective, Blair says

Deciding whether something was a "true" development was, of course, the prerogative of the teaching of the Church. But Newman also described the consensus of the whole "body of the faithful" on matters of doctrine as the "voice of the Infallible Church". I doubt if this voice is yet taken seriously enough on moral questions, or if we have yet fully digested the implications of these ideas. The tendency of some religious leaders to bundle a large number of different ideas into a bag marked "secularism", then treat it as a sinister package, is divisive in pluralist societies. It cuts the Church off from possibilities of new developments in thinking.

Jill Segger sums up the visit well in Ekklesia (20 Sep 10), reaching similar conclusions to Mr Blair. Segger finds that

it seems hard to imagine a clearer example of differing cultures failing to understand each other than we have observed over the past few days. . . . . Combine centuries of monoculture with a creed which contains the concept of infallibility, and it is scarcely surprising that there has been a failure to connect or to understand a pluralist and secular society more at home with ambiguity than with certainty. That society, in its turn, finds no point of contact with an absolutism and authoritarianism which claims a divine mandate and seems to interpret opposition as a validation of its own rightness rather than a stimulus to honest self-scrutiny.
Benedict’s clumsy conflation of atheism with Nazism and Cardinal Kaspar’s description of the UK as "aggressively secular" were without context or nuance. To be without belief is an entirely honourable and honest stance. If you have no faith, it would be a failure of integrity to pretend otherwise. . . .
Our secular society is the best guarantor of the religious freedoms of all. Theocracies will always oppress those whose consciences are not in harmony with the ruling creed. Where no confessional strand is privileged above another or above the safeguarding adjudications of a democratic state, respect for difference is enabled to flourish and difficulties have at least the chance of being the subject of dialogue rather than denunciation. . . .
If [Pope Benedict] has done something to put faith on the agenda as a deep and precious attribute of the human psyche rather than as a pathology to be deplored, then let us be glad of it. For those of us who are uneasy about power and authoritarianism, about the certainties which categorise and thereby diminish the rich diversity of human experience, about hierarchy and about obsession over human reproductive and sexual ethics to the exclusion of ardour for justice, liberation and equality, this may not have been the most comfortable few days. . . .