Hi JessN, well there is a lot of ground to cover.
The exclamation mark signifies that there is an update available. If the bundle is "managed" and you are in a production account the bundle will be updated automatically by the vendor.
But you probably see this in your Sandbox. In a Sandbox updates are not pushed at all. This is to make sure that it remains as true to the moment it was refreshed for testing purposes etc.
If it is sandbox, don't worry too much about it. Any test team will indicate if they need an update or even Sandbox refresh.