Interesting read to start building those questions to ask of your Cloud Vendors.
2 and 3, yes. Absolutely.
1 and 4 just indicate you don't understand the value of cloud computing and are an IT employee trying to protect your turf - likely to disappear quickly because the decision maker is looking at the cost factors, not fear factors that he is looking to eliminate.
At least in my experience....
Vulnerabilities are still there in cloud computing environments. In the case of small businesses you may have only moved the target to be more consolidated.