Update CHANGELOG

Author: mbostock

CHANGELOG.md

@@ -60,11 +60,25 @@ All marks now support the new standard *href* channel and *target* option, turni
 Plot.barY(alphabet, {x: "letter", y: "frequency", href: d => `https://en.wikipedia.org/wiki/${d.letter}`})
 ```
 
-The new [Plot.scale](./README.md#scale-options) method allows you to construct a standalone scale for use independent of any chart, or across charts.
+The bin and group transforms now propagate the *title* and *href* channels, if present, by default. The default reducer for the *title* channel automatically selects the top five distinct title values per bin by count.
 
-The bin and group transforms now propagate the *title* and *href* channels, if present, by default. The default reducer for the *title* channel automatically selects the top five distinct title values per bin by count. The bin transform now supports the following shorthand reducers for the bin extent: *x1*, *x2*, *y1*, and *y2*. The window transform now supports the *first* and *last* reducers to select the first or last element of the window, respectively.
+[<img src="./img/bin-title.png" width="656" alt="a histogram of penguins by species">](https://observablehq.com/@observablehq/plot-bin)
 
-The *color* scale now defaults to an *identity* scale if all associated defined values are valid CSS colors. Similarly, the new *symbol* scale defaults to *identity* if all associated defined values are valid symbol names (or symbol type objects). A top-level *clamp* option is now available to apply to all scales. When margins or insets would result in a scale’s range being inverted, Plot now collapses the range instead of producing confusing output. When the *buylrd* color scheme is applied to a (discrete) ordinal scale, it now has the expected colors (not *rdgy*). Plot now ignores non-finite values when inferring the default domain for quantitative scales.
+```js
+Plot.rectY(data, Plot.binX({y: "count"}, {x: "body_mass_g", fill: "species", title: d => `${d.species} ${d.sex}`}))
+```
+
+The bin transform now supports shorthand reducers for the bin extent: *x1*, *x2*, *y1*, and *y2*. The window transform now supports the *first* and *last* reducers to select the first or last element of the window, respectively.
+
+The *color* scale now defaults to an *identity* scale if all associated defined values are valid CSS colors, rather than defaulting to the tableau10 categorical color scheme.
+
+[<img src="./img/identity-color.png" width="640" alt="a chart with red and black bars">](https://observablehq.com/@observablehq/plot-bar)
+
+```js
+Plot.barY(alphabet, {x: "letter", y: "frequency", fill: d => /[AEIOU]/.test(d.letter) ? "red" : "black"})
+```
+
+Similarly, the new *symbol* scale defaults to *identity* if all associated defined values are valid symbol names (or symbol type objects). A top-level *clamp* option is now available to apply to all scales. When margins or insets would result in a scale’s range being inverted, Plot now collapses the range instead of producing confusing output. When the *buylrd* color scheme is applied to a (discrete) ordinal scale, it now has the expected colors (not *rdgy*). Plot now ignores non-finite values when inferring the default domain for quantitative scales. The new [Plot.scale](./README.md#scale-options) method allows you to construct a standalone scale for use independent of any chart, or across charts.
 
 The *swatches* legend now wraps correctly in narrow windows. When the *tickFormat* option is null, ticks will now be unlabeled (rather than using the default format). Plot no longer crashes when you try to display a legend on an identity color scale.