I see nothing to worry about - Apple is selling unlocked phones through Orange in France and has been selling unlocked phones through T-Mobile in Germany. Of course they will fix it - they have accepted the money for a product with certain specifications (unlocked, any SIM for a supported GSM network has to work and there is no such thing as a difference in GSM standards on a national basis, it is only caller IDs messing it up). This is a real fault with sold merchandise and it is absolutely easy to fix it (if you look at the fix available for hacked phones, it is as trivial as it can get). Apple will not leave people alone with faulty products. The iPhone will go to a couple of other markets were locked phones are either not allowed or have zero chance of significant acceptance.
Software updates follow certain quality assurance and testing standards -expecting a fix within a couple of days is understandable, but ignoring common industry standards. Of course, T-Mobile should have advised foreign buyers of possible problems, as soon as there were first reports - but they are not a professional outfit - look at their iPhone tariff descriptions for the iPhone, compare flyer, Web site and press releases and you have three different wordings. They are not remotely close to Apple's standards. I have a T-Mobile contract through a MNVO, I called T-Mobile 5 times to investigate possibilities to change contracts within this agreement (knowing it cannot be done) - I received 5 vastly different answers (from a correct "sorry, no" to "I will send you the paperwork immediately").