Amazon Web Services just got a huge shout-out today with this news. I self manage a large Web property that has 25+ AWS instances, plus some metal with ServerBeach and 1000TB.com. I also personally do all the development work on the site, as well as managing day-to-day operations and most support.

Yes, it is possible to run a multi-million dollar business by yourself with lots of servers, thanks to the cloud - in this case AWS.

Holy Cow! www.radioreference.com is that big already? Props! 570k users and 3k feeds = that infra? Streaming must be a bitch.

I love the instagram app and concept and execution, but I wonder why they even need 100+ EC2 instances (my guess is that almost all of them just serve photos). It appears instagram has little web traffic and it's not so heavily loaded with users 24/7 like facebook is.

http://siteanalytics.compete.com/instagram.com/

What you are seeing there is only the visitor traffic metrics for the landing page and the URLs shared out. You aren't seeing the back-end API centric traffic from the app to the core servers.

Twitter is in a similar situation, and according to compete data (inaccurate i know but vaguely indicative), twitter has more than 100 times more traffic, and they had ~70 servers in 2009 (http://www.quora.com/How-many-servers-does-Twitter-have). Just curious here.

I completely agree with your take on it; but pls note the entirely different problem Instagram solved vs. Twitter. If you build a real-time streaming application for pure text based objects, your stack will look very different. But collecting, storing, replicating and serving images as your primary social object != same thing.

Hence, even when Twitter 'added' photos, they went with Photobucket so as to not change the nature of their stack. It had taken them 3 years to really get ahead of their adoption curve for 'just' text.

You think API requests from all those mobile clients are some how "free"? Plus, I'd guess that they are resizing photos on the server.

Behold the power of the cloud.