I had been following several post about only getting a splash screen for Mappoint 2011. I too experienced this. I have Win7 64 bit SP1 installed and I could only get the splash screen. If I removed SP1, Mappoint 2011 works.
So I finally read Microsoft KB331796 and followed the process. I have discovered that the Logitech SetPoint 4.8 mouse drivers installed on my machine when disabled allow SP1 and Mappoint 2011 to co-exist. I can make it happen by turning the drivers on and off using msconfig in startup tab.
Today I removed the 4.8 version and installed 6.32 and MapPoint 2011 still works.