High Scalability Building bigger, faster, more reliable websites.

I don't know if it's really about meeting specific qps numbers. You can estimate your peak qps by picking a peak number of simultaneous users and the number of queries it takes to render your pages.

You can do smart things to reduce the number of queries. You can do smart things to cache so the cost of each query goes down. You can precalculate and implement other tricks.

But I think what's more important is you have a strategy for scaling. How will you grow as your user base grows? In the MySpace Architecture article they had some specific membership numbers where their architecture proved inadequate:

- 500,000 Users: A Simple Architecture Stumbles
- 1 Million Users:Vertical Partitioning Solves Scalability Woes
- 3 Million Users: Scale-Out Wins Over Scale-Up
- 9 Million Users: Site Migrates to ASP.NET, Adds Virtual Storage
- 26 Million Users: MySpace Embraces 64-Bit Technology

So I would keep these numbers in mind, think about how you will solve them, have a plan for implementing your strategies, and use monitoring to know when it's about time to transition to a new phase of your architecture.

The Flickr article has links to how Flickr thinks about capacity planning, which is very cool. For suggestions on how to scale I think there are a lot of good ideas on this site already. Maybe others will have more.

So that's kind of a weak answer, but it's a tough question.