I’ve been playing with SignalR recently and it drives me nuts that I can’t have more than a few simultaneous long polling requests open to the IIS server on Windows 7. It stops responding after about 2 clients. Even IIS Express supports unlimited simultaneous connections but we need AppFabric support.
We would seriously consider using it for our messaging solution but on a single machine developer install, we would need to come up with another solution for our many client apps.