Even though I do not personally believe that there is such thing as gold bubble right now, it is worth to read articles from people who think that there is.
Seeking Alpha: Bookstaber: The gold bubble - beware of following the herd
I happen to believe that Soros, Paulson and other high profile hedge fund managers are joining the ride because they believe there WILL BE a bubble. Right now, I do not see the average people talking about gold price let alone waiting in line outside gold dealers. This is what I expect to see if there would be a bubble. Much like what happened with Internet stocks, atleast in Finland. You got people queuing for hours to sign up for IPOs with ridiculous valuations. People who never before had invested money in stocks and did not have even book-entry accounts.
I bet less than one in a thousand people can tell me what is the spot price of gold for a troy ounce. Even with plus minus 20 percent accuracy. Related to the subject. Here is a good one from Youtube: