Wordsmithed hierarchy section of 0.7.0 release notes.

doc/release/0.7.0-notes.rst

@@ -85,8 +85,13 @@ between descendants. The ``fcluster`` and ``fclusterdata`` functions
 transform a hierarchical clustering into a set of flat clusters. Since
 these flat clusters are generated by cutting the tree into a forest of
 trees, the ``leaders`` function takes a linkage and a flat clustering
-and finds the root of each tree in the forest. Finally, a matplotlib
-extension is provided for plotting dendrograms.
+and finds the root of each tree in the forest. The ``ClusterNode``
+class represents a hierarchical clusterings as a field-navigable tree
+object. ``to_tree`` converts a matrix-encoded hierarchical clustering
+to a ``ClusterNode`` object. Routines for converting between MATLAB
+and SciPy linkage encodings are provided. Finally, a ``dendrogram``
+function plots hierarchical clusterings as a dendrogram using
+matplotlib.
 
 New Spatial package
 ~~~~~~~~~~~~~~~~~~~
@@ -112,7 +117,7 @@ unordered pairs of vectors in a set of vectors. The ``cdist`` computes
 the distance on all pairs of vectors in the Cartesian product of two
 sets of vectors.  Pairwise distance matrices are stored in condensed
 form, only the upper triangular is stored. ``squareform`` converts
-between square distance matrices and condensed distance matrices.
+distance matrices between square and condensed forms.
 
 Reworked fftpack package
 ~~~~~~~~~~~~~~~~~~~~~~~~