At my university (University of Michigan, not a "top" school but no slouch either), macro - especially behavioral macro and financial macro - is the hot new thing for grad students, thanks to the crisis.
Nothing really sparks curiosity more than a big puzzle that is important and seemingly soluble. Many independent hypotheses have been offered for the 2008 crisis, and this has surely motivated many to make their case. Given the way this totally blindsided economists (and most everyone else), clearly this is appropriate.
Yet, I'm not sanguine that extrapolations from 2008 will give us broad, generalizable, useful macroeconomic models. The crisis, to me, seems a peculiar effect from a sector with a century of good results that was then overdone. I imagine any sector with such a run will be susceptible to such a problem, but I'm not sure what other sectors would be comparable (US debt?). It's like living your life as if you are about to be mugged: preventing this is important, expertise in this area can prevent an damage if attacked, but it is still irrelevant to most people because it is so rare.
Puzzles are fun for academics because merely explaining to the ignorant (eg, undergrads) how things work is hardly sufficient to sustain enthusiasm. There's a lot we don't know, and figuring these out is fun and important. Yet, many prominent puzzles are often highly misleading. For example, the equity premium puzzle was explaining why the equity risk premium was 8%, given what we know about utility functions and the volatility of the stock market. It turns out this equity premium puzzle was vastly overstated, now thought to be around only 3.5% (and as I have argued, effectively zero). Further, solutions to this problem just amplified the puzzle as to why there is no risk return relationship within most asset classes like equities in bonds; when you fix one problem by making others worse, it's not a good solution.
So, I'm all for puzzles, but it's important to fixate on problems that are truly important. Not important with hindsight, but important for the future. Many commentators talk about the past as if it was so obvious. But the fact that 99% of stock brokers can tell you how best to invest last year still generates a useless forward looking strategy, as demonstrated by their record.
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