reCAPTCHA does not work in China mainland (it does in HK, but that's different for now). But translate.google.cn (note the .cn) works fine. Similar visual recaptchs used on Chinese services tend to focus on Chinese characters on a low resolution picture background. Training for street names? I don't know
Resolving to google.com does not resolve (gmail does, a bit, IMAP but only every few hours or days, depending on connection sans VPN).
Look under the section "use recaptcha globally" -- this is what I was referring to. However it's not clear to me if this approach enables use in China or not.
I pinged recapture.net and got a 50ms response time. Baidu would give a 20ms response time. That's on WiFi. That leads me to think the server responding to these pings is in certainly in mainland China, I think in Alibaba's IP range, but probably not a CDN. Interesting, thanks.
