Slight correction - there were some Borland tools for OS/2, but after the split MS stopped putting out new tools; but IBM did have some interesting compiler stuff too.
> In 1992, Apple and IBM cofounded Taligent, based upon Pink, an operating system with a mass of sophisticated object-oriented compiler and application framework technology from Apple. Pink became CommonPoint, the partnership was dissolved, and CommonPoint was absorbed into VisualAge starting with the Compound Document Framework to handle OLE objects in VisualAge C++ 3.5 for Windows. In February 1997, the first mass release of Taligent technology came in the form of the Open Class within VisualAge C++ 4.0 ... The original prototype which led to VisualAge was an attempt "to make something like the NeXT interface builder" within the Smalltalk/V development environment.
