I've been using Vista Bussiness for a few days now, so I'd thought I'd report my findings so far.
I'm enjoying using Vista so far. It looks better (though I know the novelty will wear off soon enough) and the side bar is great when you get some RSS feeds in there.
I'm using a dual monitor setup, and one of the things that used to annoy me in XP was that videos would stop playing when you moved them from screen to screen in PowerDVD or media player, Vista seems to have it sorted. I think they must have improved dramatically the way the videos are rendered because they even play when your cycling through applications using Alt+Tab and in the little window previews you get when hovering over something in the start bar, something that wasn't possible in XP.
To connect into the office I downloaded and installed the Cisco VPN client beta version for vista from http://vpnclient.clearchannel.com/. I haven't been able to get it running, its not a problem with the networks at either end it worked before using the same hardware and XP on my machine. When the VPN client tries to connect, it site there for a while and then returns the message "The remote peer is no longer responding". I've heard reports of other people using the Vista Cisco VPN client without problems on Vista, so looks like I need to have a dig around to find the fault.
I'm also running VMware to host a couple of virtual images of Windows XP on my machine, the only problem I've had running it in Vista so far has been using the clients with "Bridged Network" mode. When I bring up the Network Settings in the VMware manager, the OK button was disabled. That turned out to be a problem with security in Vista - I got round it my adding the _vmware_ user to the adminsitrators group in Computer Mangement, and running the VMware manager as administrator. When the virtual machine boots up, it just reports the Vmware network connection has limited connectivity. Could be a problem with DCHP and the service that VMware creates to give the Virtual Machines IPs. However, I can still get online using machines in NAT mode, so its not a huge problem for now.