Theiphoneblog carries a nice article on the reason Apple rejected the Google Voice application even though it doesn't violate any terms and services. The article goes in depth over the issue of controlling the hardware (Apple) vs controlling the software (Google & Apple so far) and how Apple doesn't want Google to take over a critical part of its phone. Just like Google is going into the OS business to make sure it gets never cut out, Apple is also building a huge datacenter to — they guess — take over some online cloud computing business of their own and be less dependent on Google for these services.