more technical info:

http://download.microsoft.com/download/1/0/A/10AD7DEC-7DAB-492B-AE28-237B56F0BFFF/InternetExplorer9RCNewFeaturesSummary.pdf

http://download.microsoft.com/download/F/8/B/F8BFDCA5-316E-4689-9399-896E04F8835E/InternetExplorer9RCProductGuide.pdf

there is the sunspider result inside the product guide