it's a bit sad that in the most decentralized media, people tend to stick to the most centralized utilities to communicate with each other (I use them too). but:

> With less sarcasm: What use is this if one already reads the blog?

none. if you don't want to use it - don't. move on.

giving users another subscription channel is not a problem. a problem appears when someone uses these closed platforms as their only communication channel, f.ex. it's impossible to move a fanpage with it's community out of facebook. when people and organization treat it just as another feed broadcast (as whatwg did), everything is fine.