Ask YC: Patent Web 2.0 invention or not?

Wondering what the communitys' thoughts on this are? Understand ideas can not be copyrighted (body of work) or patented (steps taken).

What about if your product received a lot of attention in press & has users. Could another try to apply and then successfully obtain said patent? Wouldn't the patent office reject their claim and point to the many articles on the Internet about said service/invention - state its obvious?