Hmmmm,
I am suspecting DNS is the issue here. People's ISP, local router or PC might be out of sync. It takes up to 24h for DNS servers to sync in some cases. (Especially across the globe). Yesterday and this morning I couldn't connect through the dns ppirc and now I can. Also people mentioned they never left IRC and was working fine. So this is definitely a case of DNS. You can try to reboot your router/modem or just have patience.
Or in normal human language: Your internet provider might take up to 24h to correctly connect again to IRC. People can restart their modem/routers at home.
I'll keep the news threads open until tomorrow.
Edit
Resolved for now as nobody seems to report issues.