Cloud server vs VPS

http://forums.eukhost.com/f45/cloud-server-vs-vps-virtual-private-server-11356/#.UNkQBpNevKw

2010

Cloud hosting offers many advantages over normal VPS or Semi-Dedicated server hosting services due to the number of servers that are being used for a single cluster, and if you or your business rely greatly on your website, Cloud hosting is the best suitable option for you. The enhanced architecture powering Cloud hosting solution utilize groups of high specification servers, network attached storage devices to reliably serve every web page, and image of a website. Inside each storage device, drives are replicated to each other in a RAID configuration to create a first level of redundancy.

With Virtual Private server, you will not get guaranteed resources that you will pay for, which means other user of the VPS node could squeeze in on your allotted resources but this is not case with Cloud server, you will get the guaranteed amount of resources you are paying for and it's always available when you need them. In addition to all these features, you will also get the ability to customize the resources of Cloud server anytime. VPS is not at all reliable when compared to Cloud server because VPS is based on software virtualization platform. Each platform of servers have their merits and demerits but here there are no demerits of Cloud server, so now it depends on you whether to choose VPS or Cloud server after understanding the needs and the service that you are looking.

http://www.vps.net/blog/2012/08/20/vps-vs-cloud-server/

Cloud Servers have three primary advantages over a traditional VPS.

Near limitless flexibility with resource sizes.
On the fly resource upgrades, sometimes without even requiring a reboot.
Significantly better redundancy
Centralized redundant storage