Yes, I think it's incredibly useful for communication among informed people. For example, @BullshitQuantum, which just replies to news releases with 'bullshit' or 'not bullshit', is great.

The problem is that with such a small amount of space, you can't tell what's credible and what's not unless you already know who's right... I trust @BullshitQuantum only because I can check a fair number of its calls. How is anybody not trained in quantum mechanics supposed to tell @BullshitQuantum's takes from the hundreds more that actually are bullshit?