I have used Battlegrounds for a while now as my VTT of choice. My group has found it a great tool, and its got a very uncluttered interface that concentrates on what you need the most. Also Heruca, the developer, is one of the hardest working admins I've seen. He even finds time to pop in here every now and then.
I think check out the independents first like BG, Maptool, OpenRpg and Fantasygrounds. They may not have the marketing budgets that Wizards do, but they have been putting together VTts for longer.
Torq