Comodo, like many others, gets their website blocklist from any number of aggregators. I'm not at all surprised that Qihoo is on some.
This goes back to the China Browser Wars. A number of years ago Baidu had most of the Chinese search market locked up (over 95%), and Qihoo was just a small AV company. Qihoo then developed a search engine which they combined with a browser in order to get a piece of the action. They were a tad aggressive- like the installer simultaneously uninstalling the Baidu browser, other times the Qihoo AV detecting a Baidu product as malware, etc. Not surprisingly the Chinese Qihoo browser was something approaching a rogue (and thus the website blocks).
But no matter- this strategy has lifted Qihoo from an AV company worth a few hundred million USD to an AV/Search giant (they now have about 15% of the market) worth a bit more than 10 billion USD in just a few years. Baidu is certainly not blameless, as they have used similar tricks to kill off Qihoo. My personal favorite was when they hired a hacker to publish a paper that accused the Qihoo browser of collecting personal information. Turns out that this was nothing other than malicious URL checking. Qihoo has since sued the original publisher of the paper for slander, main points can be found here:
http://www.venturedata.org/?i482766...d-security-guards-insecurity-discredit-to-sue