What is it that facebook employess work on daily? I see release of new features fairly often for something like G+ but rarely see anything from FB short of redoing what they've already done. Is this accurate or am I just unaware of a release blog?
I'm not sure I agree with your second statement in this context but I do agree with it generally in the sense that it is harmful. Obviously if one never releases a product but runs through the rolling internal releases of redoing items they've already done, then that can lead to an terrible negative-feedback loop. For a company that is well-established, however, I'm not sure the same rules apply. You don't maintain success by iterating on your existing product offering and instead need to rely on either simplifying, speeding up or offering new products/features to your clients.
One could argue that they are attempting to find alternative revenue source in these rewrites, which would be a valid argument and one I could understand, unfortunately I am not able to either confirm or quell that suggestion.
In general, I don't think they announce minor new features at all, they just deploy them slowly.