So it just _feels_ right to me that a multi-vendor policy should be a key element of any reasonably large company’s IT strategy.

Quent Herschelman is an Architect Evangelist in the Atlanta Microsoft office, and started a blog.  I love to have discussions with him about architecture because he makes me question my preconceptions.  He basically starts off his blog with something exactly the opposite you would expect from an Architect Evangelist who works for Microsoft: large companies should necessarily have a multi-vendor enterprise strategy. 

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