To use markers in Google Maps is fairly trivial, at least when you have a reasonable amount of them. But once you have more than a few hundred of them, performance quickly starts to degrade. In this article I will show you a few approaches to speed up performance. I’ve also put together a test page to compare them.
Update [2009-05-06]:This article has been updated with the addition of the utility library MarkerClusterer. The test results in the end of the article and the test page has also been revised.