One of the key things I feel is missing from Team Foundation Server is access to managing certain things, specifically Work Items, from a web-based interface. In fact, Team Foundtion Server is going to be a hard-sell to my management if this capability is not there. I have a large number of users who will need to be able to enter bugs, and it would be nice if they could do so from a web-based interface - ideally, the SharePoint portal site for the Team Project. I'd prefer not to have to buy a CAL and install the VS Team Explorer on all those machines; and while developing this myself sounds fun, I really don't have the time. I read somewhere (having trouble finding the blog post) that this feature was planned, but would not make it into V1.0.
I may not have to worry. One company is already working on a product to address this need. Take a look at TeamPlain if you're in the same boat as I am. I really wish they'd implement this as Web Parts so they could be integrated into the SharePoint portal, but I'll take what I can get. I'll post more thoughts once I get ahold of the beta version.