This mostly depends on your nationality AND ethnicity.
If you're a citizen of US/UK/Western EU, your visa issuance is typically a formality. Nobody at Chinese border crossing is going to care or ask about your itinerary, unless you come in a "Free Tibet" t-shirt or having a Falun Gong brochure in your hand. This is true for the first and all subsequent crossings. Note that you have to fill up the arrival card where you state your purpose of the visit and "intended address in China", so the typical questions the passport control officer could ask are already answered there. This is my typical experience for 6+ visits to China.
However more than once I've seen persons of likely Indian origin being seriously questioned by the Chinese passport control even when they had the US passport, and they had to show some papers (looked like hotel reservation, but I wasn't sure). So if you happen to be one, have the itinerary ready.