I noticed that apps seemed to take longer to load than they used to. When opening a program, there would be a slight pause (maybe 1 or two seconds) and then it would seem to start normally. I eventually tracked this down to the Application Experience Lookup Service service.
This service checks programs for compatibility when they are started using a database. This check is what creates the delay. By simply disabling the service, it cam be removed. Disabling it does not cause any problems generally, although may in theory case certain applications not to work as Windows cam no longer introduce hacks to make them compatible. The service was first introduced for Server 2003 SP1, then XP x64 and finally Vista and Windows 7.