This whitepaper highlights the broad range of hardware supported by Microsoft® Office 2010 and describes the significant improvements in performance available in Office 2010. Results from internal testing by Microsoft are included to demonstrate the measurable performance gains users can experience when performing common tasks using different Office 2010 applications. These results indicate that in some cases uses can expect performance gains of 90% or higher compared with using corresponding Office 2007 applications.
I just read it myself, if you’re planning to deploy Office 2010 or still need some arguments for your management, I recommend reading this paper.
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