1) Foi divulgado recentemente casos de problema de perda de conexão de usuário TMG 2010 quando rodando sobre plataforma Hyper-V R2, para isso existe um hotfix que deve ser aplicado nos servidor Hyper-V R2. Segue o link: http://support.microsoft.com/kb/974909.
2) No final do mês passado foi liberado o Service Pack 1 do TMG 2010 e recomendo que façam a instalação. As principais melhorias são:
New Reports • The new User Activity report displays the sites and site categories accessed by any user. • All Forefront TMG reports have a new look and feel. Enhancements to URL Filtering • You can now allow users to override the access restriction on sites blocked by URL filtering. This allows for a more flexible web access policy, in that users can decide for themselves whether to access a blocked site. This is especially useful for websites that have been incorrectly categorized. • You can now override the categorization of a URL on the enterprise level; the override is then effective for each enterprise-joined array. • Denial notification pages can now be customized for your organization's needs. Enhanced Branch Office Support • Collocation of Forefront TMG and a domain controller on the same server, which can help reduce the total cost of ownership at branch offices. • When installed on a computer running Windows Server 2008 R2, SP1 simplifies the deployment of BranchCache at the branch office, using Forefront TMG as the Hosted Cache server. Support for publishing SharePoint 2010 • Forefront TMG SP1 supports secure publishing of SharePoint 2010.
Segue o link para mais informações e download da atualização: http://support.microsoft.com/kb/981324