Tencent QQ called OICQ years ago comes from ICQ who don't like this, so OICQ had to change its name to the current one. Q sounds like cute, i think, this is why they didn't name they product as OO, II or CC.

btw, when tencent changed to QQ, they found www.qq.com and those related had already been registered so they had to spend much to buy the domains. maybe millions RMB.

try QQ2009preview , it looks more like WLM. luckily M$ seems not to matter this.