Custom notifications

[Alvarofg]

I wonder if it would be possible to have custom notifications. I'd like to extend it to:

1. Use it to broadcast events on my site (Such as "hey users, version 1.2 is out now". I find this less intrusive than sending an email. (also, some of us, can't actually send emails to the user unless they opted-in for it)
2. Notify users of events not coming from Q2A. Such as "User A, there is progress in topic X" (user would have sign elsewhere (yet still using his/her q2a credentials) to be informed of that)

I'm thinking being able to "insert" somewhere something like
{
"userid" : 54,
"event": "custom",
"message": "Hey $handle, there is ....",
...
}