This release adds support for gnuplot 4.0. It adds support for JPEG output files. There is no need to upgrade unless you are on gnuplot 4.0. Stay on release 1.1 if you are using gnuplot 3.x.
This release adds support for easy generation of barcharts and plotting data with dates, support for EPS files, and the ability to handle data with only one column of data to plot.