This blog is updated daily.
A general description is here.
All packages must have a namespace, and one is created on installation if not supplied in the sources. This means that any package without a namespace must be re-installed under this version of R (but previously-installed data-only packages without R code can still be used).
‘socketConnection()’ now has a ‘timeout’ argument. It is now documented that large values (package ‘snow’ uses a year) do not work on some OSes.
The default ‘colormodel’ for ‘pdf()’ and ‘postscript()’ is now called ‘"srgb"’ to more accurately describe it. (Instead of ‘"rgb"’, and in the case of ‘postscript()’ it no longer switches to and from the gray colorspace, by default.)
The ‘colormodel’ for ‘postscript()’ which does use both gray and sRGB colorspaces is now called ‘"srgb+gray"’.
Plots which are known to use only black/white/transparent can advantageously use ‘colormodel = "gray"’ (just as before, but there is now slightly more advantage in doing so).
It is eprecated to use ‘mean(x)’ and ‘sd(x)’ directly on data frames (or also matrices, for ‘sd’) ‘x’, instead of simply using ‘sapply’.
In the same spirit, ‘median(x)’ now gives an error for a data frame ‘x’ (it often gave nonsensical results).
A late change in R 2.13.2 broke ‘\Sexpr’ expressions in Rd files.
The creation of ticks on log axes (including ‘axTicks()’ sometimes incorrectly omitted a tick at one end
The creation of ticks on log axes (including by ‘axTicks()’) sometimes incorrectly omitted a tick at one end of the range by rounding error in a platform-dependent way. This could be seen in the examples for ‘axTicks()’, where with axis limits ‘c(0.2, 88)’ the tick for ‘0.2’ was sometimes omitted.
The ‘X11()’ device's cairo back-end produced incorrect capture snapshot images on big-endian machines.
‘loglin()’ gave a spurious error when argument ‘margin’ consisted of a single element of length one. (PR#14690)
‘stack()’ and ‘unstack()’ converted character columns to factors.
‘unstack()’ sometimes produced incorrect results (a list or a vector) if the factor on which to un-split had only one level.
Non-blocking listening socket connections continued to report ‘isIncomplete()’ as true even when the peer had closed down and all available input had been read.