Before I do I again want to point out, that I am not being payed by rackspace for this post, and I do not currently use any of these products personally although I have had clients who have used rackspace in the past. I do plan to use this product in the future.
Also Rackspace is only one of many who offer cloud services. Please don't flame me with X does this too and costs this much or have you seen y.
So Cloud Sites.....
When you sign up and host your website on cloud sites, it is just like hosting in a shared, virtual or dedicated environment except, load balancing, clustering, and redundant storage are all inherited by your application automatically, without any effort.
So as your web presence grows your site scales automatically, without having to rent, buy or lease new hardware ahead of time.
So what is the catch...
The catch is simple your monthly fee you pay is flat but as you start to use more ram, processor and bandwidth, you are charged an extra fee. It is like a cellphone pay as you go plan. The cool thing is that if you start using less resources the extra fees are not charged. The flat fee price includes cpu cycles, bandwidth and storage already, you only pay extra if you go over the allotted amount.
What technologies do they support...
As you can tell from my blog I focus in the .Net world. So yes you can run your .Net web apps, both MVC and Webforms. They use IIS 7, .Net 3.5 and lower, Windows Sever 2008 and Sql Server 2008.
They also have Linux path that runs Debian + Red Hat, Apache, MySQl, php, Perl and what not. I cant speak to these choice since I do not know enough about this path.
How do I get my app out there....
Setup is a process of walking through a wizard that guides you to deployment of your application. Reading through the FAQ it seems that your site is very customizable.
I was going to provide pricing information however they removed that section from their site and force you to talk to a person to get it. I do have some of the old pricing though so this would be more of a guideline than what is most accurate.
149.00 per month
0.22 per gb of bandwidth first 500 free
0.01 per cpu cycle first 10000 free (they had a stat that this number was able to host an average website or a small data intensive site)
5.00 per 100mb sql server file size
I don't have the cost for hd storage and what is included. :(