I totally agree that an email in that situation is not informative. I have worked in parts order/distribution before and there is nothing worse than chasing your tail sending off notifications.
However when I was in that job we overhauled our service delivery charter to a very simple "tell them before they ask" premise.
For an example: If I was waiting for an item and only had a vague time frame. It's getting towards or past that time frame, I'm getting angry.
Now here is where we diverge,
Scenario 1) I make the phone call, they tell me they just started shipping today and I will see my item soon. I think "Bull#$@#, they only shipped it because I rang them"
Scenario 2) just as I am picking up my phone I see a new email "Just a quick group email to let you know we have received the item and will be shipping all orders over the next week starting today. Due to the high demand for this product we will be flat out, please allow 2 weeks for your item to arrive.
Just the fact that you are contacted by the supplier first will (in general) completely change the attitude of the customer.
Like it or not business/client relationships are symbiotic, both need each other to survive.
I always hated the entitled customer, and they will always exist, but it's just good business sense to eliminate as much potential conflict from your end.
In summary:
1/ Yes, people should calm down and let the business get on with their job
2/ Yes, the business should do everything in it's power to make the customer comfortable with their purchase. They are buying a product unseen from the screen of their computer and you can not calculate how much that customer is worth to you.
In terms of social media, the world is run today on social media and it can be the making or breaking of a small (Sometimes big) company.
Negative feedback campaigns have brought many big companies to the negotiating table after refusing any wrongdoing via personal email.
It's a positive thing for companies to employ social media as long as it incorporates a simple, record-able medium of private business to client communication.
................Or I'm completely wrong