Various ISPs, including Comcast, Sonic.net, and a few others aggressively cache DNS entries (including SOA records) for longer than the 30 minutes we specify.

If you continue to have problems where the site completely times out - you get nothing back - then use better DNS servers:

https://gist.github.com/kogir/7237218

Yes: https://news.ycombinator.com/item?id=6640210

I am from Houston and I noticed the same.

- Yes, I believe so.

- It was down 3 times for me today.