Uh... as I read it the point of this app is the the whole world is able to read your messages. This app is just the existence proof that all that is required is access to the raw packet data.
Clearly most people are going to "trust" Apple Computer more than this app vendor. But the point is that such trust isn't worth anything. The data is hanging out there already.
Huh? So, does the existence of an open-source reimplementation of early versions of SSL also imply that if you had access to the raw packets you can read anyone else's SSL stream? How about if we first require the data to be sent in the clear to someone who refuses to tell us how DES works, but is willing to provide a web service that implements it? This app is not by any stretch of imagination proof that the protocol on the wire is not encrypted. Yes, that might be the case, and we might learn some interesting things at pod2g's talk on iMessage at HITB (I'm definitely looking forward to that), but that would be totally unrelated to the existence or possibility of this app.
It is not only one person, it is not only Apple servers reading all your messages. It is in fact the whole world. Through Apple gives it to NSA which hands it over to various other agencies, GHCQ, FRA, your data ends up in Israel. Your data is already a goods traded with on the international market.
Why not increase the competitiveness of this Chinese actor, you will get better service in the future? More competitive - better service.
The NSA has already sold your CC on the black market. Its just that the buyer hasnt used it, because they cant use it without getting penalties. Penalties which this Chinese vendor would succumb to as well.
Now are you going to say you trust Israel more than the Chinese, they wont misuse your CC, and if they did, its still better than trusting a Russian vendor?
Not. This. Again.
Because one person can read your messages, it doesn't mean that the whole world should be able to. One happening doesn't mean the other is okay.