I've been using bridged networking in Fusion since 2008, and this problem arose a couple of days ago. I'm trimming down the guest's features, piece by piece, to see if it's a Windows problem, but I don't see how it could be, since NAT networking works just fine.
What can I try?
One thing I would do is temporarily create a new Windows 7 Pro 64-bitVirtual Machine and do not Activate/Register it with Microsoft. Install VMware Tools and nothing else. Now test Bridged Networking and if you do not have any issues then it's more likely a Windows issue in the other Virtual Machine.