Tencent is the most sucesful Chinese internet firm with a market cap of $80 BILLION (4x Yahoo!'s current value).
In terms of value to investors Oliver Wymann recently ranked them as the highest value creating firm in the Telecom and Media space, followed closely by the South African Media conglomerate Naspers...which happens to own 40%+ of Tencent.
Their success comes not only from their massive number of users, (355M according to this recent post by Bill Gurley of Benchmark Capital) but more importantly by the revenue they generate per user ($3.38 in real dollars, which Bill equates to $17 on a cost-of-living adjusted basis).
Maybe it's a cultural thing, maybe it's an education thing, but QQ's over the top, in your-face selling of Avatars, gifts, virtual goods and cute penguins... but it works! Tencent's mobile deals and ability for users to extend their network from PC (internet cafe as primary PC based access point) to mobile with significant success.

