You don't need to be too concerned about the Cloud...
1. Because your firewall rules suck
2. Because you are not applying patches
3. Because your users are all administrators of their desktops
4. Because you trust those nice charts with HIGH/MEDIUM/LOWs
5. Because you have malware active in your network…
6. …and you can’t see what it is doing…
7. …but you think the next shinny box will solve it
Maybe when you fix those you can start worrying if the Cloud is secure enough for you.