You can view release notes for each release of the PowerShell Junkie here. You can also download source and binary distributions of the plug, though for obtaining the latter it is recommended to use the update site instead.
Release 1.0.0 is the initial release.
PowerShell Junkie 1.0.0 (21 March 2009)
org.ahmadsoft.powerscriptjunkie.feature_1.0.0.bin.dist.zip Binary distribution.
org.ahmadsoft.powerscriptjunkie.feature_1.0.0.src.zip Source distribution.
source Browse the source online using OpenGrok.