In a week devoid of new software releases, Japanese consumers continued to snatch up Nintendo's 3DS console, while Sony's new Vita remains flat.According to tracking firm Media Create, 3DS sales jumped from 197,952 to 240,819 in the week ending January 8, putting lifetime sales in the region just past 4.5 million.Sales of Sony's Vita, meanwhile, stayed flat, its 42,915 sales just slightly above the prior week's 42,648. Media Create's estimates put life-to-date sales as of January 8 at 482,901, but Sony itself said the following day that sales had broken the 500,000 mark.For software, the sales charts were topped by four 3DS titles, namely Nintendo's Mario Kart 7 and Super Mario 3D Land, Capcom's Monster Hunter 3G, and Level-5's Inazuma Eleven Go: Shine / Dark, according to a translation on the NeoGAF forums. With the exception of Inazuma Eleven, all of these titles are now million-sellers.The Vita meanwhile continues its struggle to sell retail games: no titles managed to crack the top twenty, which saw all but four titles represented by Nintendo's three current systems. It should be noted however that Media Create tracks only physical retail sales, and not potential digital sales for the console, which sees all titles released in both formats simultaneously.