I'm sure performance varies at certain times but you can check the performance of a website, or a single web page, using this site..
http://www.websitetest.com/It allows you to test the performance, with a variety of browsers, from multiple locations around the world.
My tests have shown that with a thread that is heavily loaded with local images, this site performs better than ~80% of websites when accessed from within the USA and better than ~55% of websites when accessed from Europe.
It takes me ~3 seconds to download a thread that is heavily loaded with images. I have 30mbps download speed. My tests from Europe benchmarks out at 5-7 seconds to download the same page.
If anyone notices the site slowing down, they can use this site to test and post back the results here.