That comparison's a bit of a stretch. This incident wasn't over abstract principles (e.g. liberty or democracy); it was a reaction to an unjust exercise of eminent domain by the government (and to the arrest of those who complained about it). Plus, the Tiananmen demonstrators didn't throw Molotov cocktails at the riot police as these villagers did (IIRC, the police didn't start shooting until the villagers did this).