cloud hosting is the future of hosting, similar concept to desktops going virtual, the hosting is done on a mass scale so that you pay for only the exact elements you use, decreasing your costs and if you get huge spike in traffic, its absorbed, some other examples below from securedcloud
http://phoenixnap.com/secured-cloud/...d/features.php
Using the innovative Secured Cloud, you can:
Provision customized cloud virtual machines on-demand
Easily configure and horizontally scale servers to address traffic spikes
Scale RAM allotment on the fly as need dictates
Load balance your VMs and physical hardware with F5 Networks' technologies
Turn your services on and off instantly to meet changing demands
Manage everything through our custom-developed user interface
Convert IT CapEx to OpEx; pay only for what you use
Easily deploy a virtual firewall for an added layer of security
Use APIs to efficiently integrate applications into the cloud