Good to know I wasn't the only one yesterday (also reading through the thread, good to know I wasn't the only one with problems a couple weeks ago when I was booking a different itinerary!). Oddly, I tried on an iPad after trying on Chrome and Safari on the Mac, and I was able to book a flight while the website was still down when accessing it on the Mac.

On Twitter they confirmed that the website was down when someone tweeted at them, and encouraged that user to try again in "a couple hours." I wish their Twitter feed would have some kind of dashboard at the top to show whether the site was working properly, given how often the website seems to have issues, because it's a giant waste of time to keep trying every five minutes to see if the site is working or not. I know they would never do this, but would be a great customer service!