System Information
Windows 7 Pro 64bit / 8GB RAM / NVIDIA GeForce GTS 360M
Blender Version
Broken: v2.70.5 198f5e5 (blender-2.70-198f5e5-win64-vc12.zip) Worked: v2.70a f93bc76 (official release blender-2.70a-windows64-vc2013_preview.zip)
Short description of error
The Sapling Generator Addon doesn't create a proper tree structure in the 3D View; a spiky armature is instead visible departing from the origin point. It was already broken in version hash d8282da but I haven't kept previous builds so I cannot tell exactly when the Sapling Generator stopped working properly. The issue affects both the Win64 and the Win64-VC2013 versions of Blender.
Exact steps for others to reproduce the error
Open Blender, activate the Sapling Addon in the Preferences, remove the cube, add a tree from the Curves menu. The screenshot below displays what is being generated in the 3D Viewport: