Meanwhile in the current New Scientist:
Why Darwin was wrong about the tree of lifeThe New Scientist is - rightly IMHO - at pains to point out that the problems it highlights with the "tree of life" provide no ammunition for the creationists or other opponents of science.
The tree-of-life concept was absolutely central to Darwin's thinking, equal in importance to natural selection, according to biologist W. Ford Doolittle of Dalhousie University in Halifax, Nova Scotia, Canada. [...]
For much of the past 150 years, biology has largely concerned itself with filling in the details of the tree. [...] today the project lies in tatters, torn to pieces by an onslaught of negative evidence. Many biologists now argue that the tree concept is obsolete and needs to be discarded. "We have no evidence at all that the tree of life is a reality," says Bapteste. That bombshell has even persuaded some that our fundamental view of biology needs to change.
Personally, I think it is the BBC 4 programme that provides ammunition to the opponents of science. Over-simplification and excessive claims in the long run undermine trust in science.
(There's an obvious information angle to this in 'bio-informatics', but I also think that what's emerging in the New Scientist article links to David Weinberger's 'Everything is miscellaneous', in the sense that the 'tree of life' was an 'old style' categorisation. Real evolution is much more miscellaneous...")