In December I moved this site back to WordPress.com after using a self-hosted site for a couple of years.
I’ll write more about the pros and cons of switching back to WordPress.com later. For now, here’s clear evidence of one benefit: Pages from my WordPress.com hosted site download more than five times faster than on my self-hosted site.
The graph comes from Google Webmaster Tools. Before the switch it was taking an average of 2200 milliseconds to download a page. Now it takes around 400 milliseconds.
This isn’t the whole story. I tried two hosting companies, the 2200 millisecond average was from the second, more reliable host. I switched to that company from an earlier host, where the average download time was closer to 3000 milliseconds. In both cases I used caching - the speeds would have been much slower without it.