I've read on the SBS official blog that the DNS server server address for a SBS client should behave like explained here: Understanding Client Networking in SBS 2011 Essentials
On our case (3 Lenovo laptops running 7-64bits), the DNS server is not set to "automatic" when the SBS is not available (ie at home). This prevents from accessing the web. To be able to resolve names (when outside the SBS domain), I have to manually set "Obtain DNS server address automatically" on the IPV4 interface properties (each time I go out of the domain). This is not very handy. It seems that the "polling SBS" feature on the client (performed by the Windows Server LAN configuration) is not working properly. Any ideas?