In the example Igor sent, the content will be replaced by content from server, so hiding the loading msg should work fine...
The problem is, that it's more likely you want to display the "loading" msg again when loading another partial :-D
Checkout the code and $status service - this service displays status messages like "Saving", "Deleting", "Loading" etc...
Note that it uses $browser.notifyWhenNoOutstandingRequests which is not public api. In new $xhr you will be able to use $xhr.pendingCount() to implement much easier...
V.