On the one hand, I like how broad this is. It purports to handle a bunch of different types of events, and all you have to do is describe what you want in plain English.
On the other hand, I'm skeptical about how well a service can execute when it has to handle such a broad range of alert types.
I've written a lot of notification-type stuff (e.g. monitor a Twitter feed for when my book titles are mentioned, monitor a bank account for unusual activity, monitor a blog without an RSS feed for new posts), and it's definitely not a one-size-fits-all type of service. If GetNotified has to write new code for each monitoring request, I would imagine the subscriptions would have to run for a good long while before they make a profit.
P.S.: A little free copy editing help: There's a typo in "If you are in doubt, just submit the request and will let you know if it can be done or not."