The Bank of Japan has ignited the financial markets. But it may not light a fire under Japan's real economy.

The BOJ's announcement that it will substantially increase the purchase of Japanese government bonds, and venture into equities and other assets, had an immediate impact. Japanese shares gained 2.7% Friday and the yen fell sharply against the dollar after the bank said Thursday it will unleash an additional ¥50 trillion ($523bn) of liquidity in each of the next two years. JGB prices also swung wildly and some other Asian markets fell - Hong Kong's Hang Seng lost 2.7%, for instance - with investors perhaps looking to reallocate funds to Japan.