We have 2 upcoming products to handle this. This first, is our hosted TFS instances (hosted on our infrastructure) will have a real-time view of all leases, how many remaining, etc. This is coming very soon (you'll see a blog post about it when it's released).
Later on we'll have another product coming (TurboFloat Server Manager) that will let you query TFS instances (where ever they're hosted -- even on our servers) to show real-time statistics.
So, the best solution is coming very soon in our hosted TFS instances.