I've been having a look through the reporting functionality included in Microsoft Forefront Threat Management Gateway to find that not much has changed from ISA Server 2006. There is some new information regarding the newly implemented URL categorization and threat management technology, but there is very little flexibility or customization for those with reporting requirements beyond general overviews cluttered with irrelevant information. Here is what I consider to be the 8 main limitations of Microsoft Forefront TMG's reporting functionality.
Today I was asked how to transfer one report in the web module to a different user. The obvious reason for this is when someone leaves your company, the reports they had access to need to be transfered to the new person taking over their role. Unfortunately there’s not an easy way to do this via the user interface yet, but it is a planned feature. In the mean time, you can do it by editing an XML file manually.