Yesterday we announced acquisition of Team Plain. This is really a great move by us. I have seen Team Plain and I feel it is a key component in increasing reach of TFS in non development community. Having a web access to all the major features especially the Work Item tracking system is key to success. I don't think we can accept any non developer to install and use Visual Studio. This is a great move by us.
You can read more at Brian's Blog or MSDN