Phew, we'd not heard of anyone else with this issue but it still made me a little worried when you mentioned the problem. I'm pleased you've got it working now though, thanks for letting us know.
my ISP is using mcafee, which apparently is marking your site as "dangerous". I'm not 100% sure how they are doing this, I assume something during DNS lookup.
Thank you, that’s quite worrying, I hope it doesn’t affect many people. I don’t suppose there’s any way of you flagging it as a bug as a customer is there? (I hope that doesn’t sound cheeky!)
I talked to Century Link, and realized that they install a Mcafee "anti-virus" tool on their routers. I disabled this on the router, and the problem went away.
You might want to talk to Mcafee about their classifying your site as dangerous, or just curse them out like I've done when they listed my software as malware. For what it's worth, they do the same to emacssurvey.org so it's not just you :)