Gnuplot Version 4.6.6 (September 2014)
gnuplot-4.6.6.tar.gz source files for all operating systems
announce.4.6.6 Release notes
gnuplot.pdf User Manual
Binary packages for Windows
gp466-win32.zip windows binaries gcc-4.9.0 (MinGW-w64 32 bit dwarf)
gp466-win32-setup.exe self-installer package of above
gp466-win64.zip windows binaries gcc-4.9.0 (MinGW-w64 64 bit seh)
gp466-win64-setup.exe self-installer package of above
gp466-cygwin-x86.zip Cygwin x86 (32 bit) binaries prepared by gcc-4.8.3
gp466-cygwin-x86_64.zip Cygwin x86_64 (64 bit) binaries prepared by gcc-4.8.3
The is the last incremental update planned for gnuplot version 4.6.
Final release of version 5.0 is expected by the end of this year.
Preliminary release candidates version 5 available for testing.
Version 5 Release Notes