Japanese stocks have been on a roll, and the Nikkei (NIKKEIINDICES:^NI225) hasn't let up its rise this week. The index rolled to gains of 1.3% over the past five days, fueled by Friday's surge of more than 1.4% after the confirmation of new leadership at Japan's central bank that will only provide more ammunition to Prime Minister Shinzo Abe's inflationary goals. The Nikkei's up more than 15.8% for the year and investors are happy, but will the good times roll on? Let's get caught up on what you need to know.

Abe takes the BoJ
The Nikkei got its first bounce when Japan's Parliament confirmed the Bank of Japan's new governor, Haruhiko Kuroda. Observers expect Kuroda to go along with Shinzo Abe's dovish monetary plans that have so far sent the yen into a nosedive against the dollar this year. Kuroda and his new team will have their first policy meeting at Japan's central bank next month, and all eyes will be watching to see if any further easing comes as a result.

Eisuke Sakakibara, the former Japanese vice financial minister of international affairs in the late 1990s, said earlier this week that it would be "unlikely" that the yen-to-dollar exchange rate would soar past 100, but little has slowed down Abe's currency devaluation so far in 2013.

Other nations haven't been as happy about Japan's aggressive moves, however. A group of U.S. lawmakers spoke out against Japan's joining of free trade talks in the U.S. -- proposed Trans Pacific Partnership (TPP). The TPP originally revolved around America and 10 other Pacific nations establishing a free trade deal, but Japan's willingness to join the discussion raised eyebrows over the country's regulatory barriers that have in the past restricted American autos from the Japanese market.

Still, the talks haven't hurt Japan's leading automaker, Toyota (NYSE:TM). The auto stock was named individual Japanese investors' most popular stock in a survey by Nomura Holdings (NYSE:NMR). Toyota's shares have risen more than 7.8% on the NYSE, but the company's Nikkei listing has shot up by a whopping 25% to outperform the index. Toyota already retook the global industry lead from rival GM (NYSE:GM) in January, and while GM's surging ahead of Toyota in China with the ongoing Chinese-Japanese territorial dispute, the U.S.'s top car company faces plenty of challenges of its own. Further weakening of the yen will only help Toyota expand its worldwide lead as it advances internationally.

The falling yen will likely help out the financial sector as well, and Nomura's been feeling the love recently. Japan's leading financial institution's shares jumped almost 42% over the past three months, although it did take a blow earlier this week when Bank of America (NYSE:BAC) poached its Australian head of mergers and acquisitions. Mizuho Financial Group (NYSE:MFG) has also been having a great time recently, with shares up more than 39% over the past three months. The financial stock ranked as Japanese investors' second most popular stock after Toyota in Nomura's study, and with the company's efforts to boost its operations in Latin America -- it hired four Latin American executives this week to further that goal -- investors should feel good about Mizuho's aim of expanding into emerging markets.

Is the best yet to come for Japan's top stock?

Fool contributor Dan Carroll has no position in any stocks mentioned. The Motley Fool recommends General Motors, and owns shares of Bank of America. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.