A source that Reuters says is close to Google believes the company doesn't think the timing is right. Google wants its customer to have a positive experience with their new devices, and that may not be possible at the moment considering the circumstances.
There are already two Android devices available in China -- the OPhone and the Dell Mini 3. Both of them are being sold by China Mobile. The delayed devices, one from Samsung and one from Motorola, were to launch with China Unicom.
Google's trepidation makes sense in this situation, but Samsung and Motorola are going to suffer directly as a result of the decision. Knowing that, are Google's actions here cool? Both Samsung and Motorola have invested time and resources to develop, promote and prepare these two devices for launch (which was supposed to happen tomorrow). So has China Unicom. The postponement is indefinite. Are these brand new devices from Samsung and Motorola, re-badged devices that are being marketed elsewhere? That information is unknown. How will the delay affect sales?
Any way you look at it, Google's partners are getting the short end of the stick in this particular situation.