Updating database schema or interfaces between services should take time if you want to limit the downtime. The extra work involved might mean you should accept a little downtime instead. It probably should be on a case by case basis rather than a blanket policy.

Interesting list. Definitely to keep in mind when developing and deploying a web application.

Interesting take. Will it lead to paying more attention to performance in software? Will it be the rise of the specialized CPUs? Time will tell.