Look at your visa carefully. There are two types of terminologies issued by Chinese missions, depending on where visa was issued.

1) "Enter Before" (+ date). It is as Tauphi says above. This tends to be the most common terminology seen now, at least with most L and F visas. There will be no hotel issues with this kind of visa, as long as you are still within your designated duration-of-entry.

2) "Valid Until" (+ date). With this type, you need to pass through China exit immigration on/before that date. Or, get an extension as described above by Chinatrvl, at the Public Security Bureau, about 5-7 business days before your expiration date. Note two things about extensions: (a) It is more trouble to get them in larger cities, especially Beijing and Shanghai, due to the request for proof of funds (USD 100 or equiv per day x 30 days) in a CHINESE bank account. If you need an extension, get it in a smaller city or town. (b) It will cost you money. For US passport holders, it will be the equivalent of a brand new visa--$140. For other passport holders, can be as little as RMB 160, or somewhere in between those two extremes.