AT&T building out network capacity to prevent exodus to Verizon's iPhone?

So this is what all those "yo' network's so slow" jokes were about. The Wall Street Journal has today penned a story framing AT&T's hefty recent investments in building out its network as a defensive move against a "huge exodus to Verizon" when its rival gets the iPhone. These preventative measures include working with Apple on streamlining the iPhone's network load, and infrastructure spending that is expected to be $2 billion more in 2010 than in 2009. The WSJclaimed yesterday that Apple was working on a CDMA version of its iPhone that could hit mass production as early as September. However, concluding that the iPhone on Verizon is a done deal seems something of a stretch. Sprint has shown a remarkable ability to attract cutting edge phones, and China Unicom's exclusivity agreement is about to hit its precarious first anniversary about the time this handset is set to roll out. Still, setting aside the analyst blather and extrapolation, the picture that emerges is of AT&T feverishly patching up its service offering in the face of a rapidly expiring exclusivity arrangement.