Thanks, but won't an app be available?. I'm getting notification on the lock screen from many other apps.
Oh, if you want an app that notifies you for every RSS entry, that's different! (not sure which one does it and it's potentially annoying if you have a very active RSS feed) An app can push a notification (and you can decide if you want said notification to display details or not) to the lockscreen, but cannot create a widget there.
Yes - that's what I'm after, something which pushes a notification to the LS. It doesn't need to show a full-fledged widget.