@GaelVaroquaux Fixed a bug in the example, added L2 normalization and linked it. It's now much better than raw k-means:

    Homogeneity: 0.376
    Completeness: 0.489
    V-measure: 0.425
    Adjusted Rand-Index: 0.369
    Silhouette Coefficient: 0.007

100 LSA features:

    Homogeneity: 0.570
    Completeness: 0.605
    V-measure: 0.587
    Adjusted Rand-Index: 0.562
    Silhouette Coefficient: 0.036

(This is one of the worst runs; there's quite a bit of variance, apparently due to k-means initialization.)