A family of Microsoft relational database management systems designed for ease of use.
I suspect that what you're really asking is if it implemented multiple threads (which the operating system can schedule across multiple cores), the short answer is that it hasn't been discussed or mentioned anyplace that I have seen. One of the things that did change was that 'Office 2010' supports graphics acceleration (i.e. can take advantage of the GPU on smart graphics cards). Where this can help with the rendering (the drawing) it probably doesn't add to some of the bottlenecks in complex Visio drawings. v2013 has a number of performance enhancements. The one I find most interesting is the integration of the 'Office' drawing package, which means that the rendering enhancements put into Powerpoint/Word/Excel now become available to Visio (i.e. smartart).
Short answer - Drawing performance is still pretty much in the hands of the person creating the drawing and making informed decisions on how to get the best out of the tool.
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