The #1 reason I ignored notifo is I couldn't understand the business model. As such, for our internal systems, we notify via SMS, email and jabber. Things that I know will still be around in a year.

Why the past tense? It's still going. As far as I know, they plan to charge for over 10k notifications/mo when they get a bit more traction. I use it on my Android phone and it's fantastic.