Not for me. I've been trying for a few days with 2 browsers (Chrome & FireFox). Is it just that it's very slow and I'm not patient enough? I wait 30 secs which is long enough for every other site I have ever visited.
As I have two different ADSL providers I can confirm that situation. With one provider it seems impossible to connect to ninjatrader.com while with the second provider that web site opens as fast (or slow) as any other. At the beginning I thought that they are bancrupt and therefore their web site is down.