ggplot2 0.8.4 (2009-12-08) ----------------------------------------

* aes and aes_string both convert prefixes to full names
* aesthetics: corrected list of aesthetics to include american spelling of
  colour as well as base R abbreviations
* aesthetics: fix bug in detecting which aesthetics are calculated
* aes_string treats NULL as "NULL"
* annotate now works with missing x and y (e.g. for geom_rect)
* continuous scale limits now automatically sorted
* coord_polar: fix bug if breaks not all inside limits
* facet_wrap: can now specify both ncol and nrow without getting an error
* facet_wrap: now works with statistics that produce both x and y values (e.g.
  stat_qq)
* fullseq now adds additional break on bottom if necessary, so that the
  include.lowest argument in cut never comes into play (this the source of a
  potential bug in histograms)
* geom_boxplot: alpha now affects fill colour of boxes only
* geom_path correctly switches to segments if varying alpha used (thanks to
  Karl Ove Hufthammer for the report and Baptiste Auguie for the fix)
* geom_point: the alpha aesthetic now also affects the fill.
* geom_ribbon always sorts input to avoid problems with certain pathological
  inputs
* geom_smooth was incorrectly applying alpha to line colour in the legend
* nullGrob renamed to zeroGrob to avoid name conflict with grid
* position_collide now works with missing values
* position_stack: fixed bug in detection of overlap for negative values
* scale_discrete_position now uses drop argument to force dropping of unused
  levels
* scale_gradient, scale_gradient2 and scale_gradientn now uses label
  parameters, if supplied
* scale_x_inverse, scale_y_inverse now actually work, and added recip as alias
* stat_qq now correctly groups results
* stat_smooth will not try and fit a line to 2 or fewer points (previously
  didn't try for only 1 point)
* stat_spoke now works with reversed scales
* grouping: now consistent between different geoms (Issue #33)