In a Perfect WordPress World..

When I install WordPress on lower-powered servers, such as a VPS, or MediaTemple (don’t use MediaTemple*) I generally activate a series of plugins that offer caching and off-loading of resource-intensive tasks to third-parties. For instance, the core commenting system in WordPress is a mess, so I disable it and install Disqus. Search functionality is also something I disable, setting up something like Adsense for Search, or Lijit. My choice of providers might not be the best, but they’re free, and stable enough to load even when Digg, Reddit and StumbleUpon blast your site with 300,000+ users in under 6 hours. The best decision I’ve made was to require MaxCDN for all WordPress installs. Excellent, excellent service.

* MediaTemple recently got hacked and had to change hundreds of thousands of users MySQL passwords, and their weekly chain of emergency maintenance procedures got old two years ago.

Your mileage may vary, however.