  Wikipedia articles are by definition never finished: at any moment their
content can be edited, or discussed in the associated talk pages. In this study
we analyse the evolution of these discussions to unveil patterns of collective
participation along the temporal dimension, and to shed light on the process of
content creation on different topics. At a micro-scale, we investigate peaks in
the discussion activity and we observe a non-trivial relationship with edit
activity. At a larger scale, we introduce a measure to account for how fast
discussions grow in complexity, and we find speeds that span three orders of
magnitude for different articles. Our analysis should help the community in
tasks such as early detection of controversies and assessment of discussion
maturity.
