Netbeans 6.5.1 here. Mercurial is listed under the 'Versioning' menu (probably installed via Tools->Plugins). The python plugin is there too, although that's

Netbeans 6.5.1 here. Mercurial is listed under the 'Versioning' menu (probably installed via Tools->Plugins). The python plugin is there too, although that's listed as beta.