It looks like the folks at Nintendo HQ have cause to bake a celebratory Wii cake, as Reuters reports that the company is now Japan’s fifth-biggest in terms of market value after word of solid earnings performance pushed shares higher in trading today. According to Reuters, the company’s market value now stands at ¥8.69 trillion (or about $72 billion), which places it ahead of both NTT and Honda Motor Co. The jump, of course, is largely due to demand for the Wii and Nintendo DS, which has also caused the company to up its operating profit forecast by a hefty 37 percent to ¥370 billion ($3.1 billion) for the year to March 2008. Unsurprisingly, Nintendo doesn’t see that demand letting up anytime soon either, with it now saying it expects to sell 16.5 million Wiis in the current business year, along with 26 million DSs — both numbers of which are 18 percent higher than previous forecasts by the company.