I'm currently having an app in private beta and I'm now ready to launch it.
Should I just make it available on my website or should I seek out for a blog that announces the launch to get some media coverage?
To answer your question which if I am understanding it correctly is getting the word out in a controlled manner so everyone is not coming to download/purchase your app but having people that have a real interest in your app and can provide some real feedback.
In that case I would offer the following path (I am not sure of your resources so I am assume its just you).