Here's one response to the gold bug arguments, by Nobel prize winner Krugman:
http://web.mit.edu/krugman/www/goldbug.html
Even libertarians like Arnold Kling don't really have much time for the gold standard:
http://econlog.econlib.org/archives/2007/01/the_new_deal_an.... (and in other articles)
Generally, it's not regarded as territory for "serious economists", although of course it is always possible that serious economists are wrong.
Both are much better than the Krugman piece.
The gold standard, having been around for 2,000 years, is the constant subject of serious study by economists.
Incidentally, I think the "because we did it that way for a long time" argument is a terrible one. There are plenty of things we've done for a long time as humans and as societies that aren't very good, and are worth discarding. I don't think the gold standard is a good idea myself, but in the arguments for it, there are better ones than that one.
I personally haven't met anyone who has argued for the gold standard and has read it although that may be a comment more on the academic backgrounds of the people who used to write pro-gold stuff and stuff it into my inbox back in college than the theoretical basis of the argument. So while gold may have a place as an investment (especially as a hedge against inflation) in large part people who spend considerable breath on extolling its virtues using words like "intrinsic value" and "stability" and "natural" are kooks. Their choice of the word "natural" is also odd since gold coinage is hardly more natural than paper and in fact is less easy to control the asset base.
When economists talk about not repeating the mistakes of the 1930s, they are by and large talking about the importance of maintaining liquidity in the system to prevent deflationary spirals, and avoiding liquidity traps. They are also cognizant of Keynes' proof that Say's Law does not work once people want to start doing things like holding liquid assets, and the dismal performance of things like the zero-inflation policy in Canada and other countries through the 1990s.
I'm amazed by the number of Internet libertarians who have jumped on this bandwagon.
It appears (to me and probably others) that part of the current problems the USA is facing is due to a govt that grows and grows, without a method to have a feedback loop that would restrict it - currently it seems the answer is to just print (electronically or physically) more $100 bills (which cost about 4 cents to make).
The lesson the Keynesians took from this episode was not to go on a gold standard in the first place. The lesson the Austrians took was that government should not dilute the currency. Since all government's prefer to dilute the currency, and most "mainstream economists" are government funded, mainstream economists are almost all Keynesian, not Austrian.
The best two articles I've read in defense of gold are these two: http://unqualified-reservations.blogspot.com/2007/11/who-hec... and http://unqualified-reservations.blogspot.com/2008/02/return-...