We have a decent-sized server estate: several ProLiants, plus IBM BladeCentre and SANs running a VMWare environment. Due to an imminent premises move, we're not going to have enough space for a server room, so I've been looking at moving everything out to a colo. My boss is more keen on the idea of cloud-hosting everything, which would include a couple of high-traffic websites (about 9m pageviews/month), our Exchange sever (about a million clean emails sent/received monthly), as well as file/print/AD/all the ususal stuff. This doesn;t sound like a good idea to me, but I'm new to the ways of the cloud. Can anyone offer any advice?