No need to remember any username or password. You are identified using a UUID meaning that you can generate a new identity whenever you want.
Pushjet is built with self-hosting in mind. Heck, it's encouraged. You can grab the Pushjet server and host it on your own server. This means that you are in control.
The Pushjet API is super easy to use. It allows developers to connect to it multiple ways making it super easy to send notifications and write applications that can receive them.
More clients are under development; Web, Linux (GTK), Windows and OS X.