Jeff Bezos has scored a huge win in his investment portfolio today, after enterprise software maker Workday soared in its IPO debut. Workday develops human resources software, and is based in the Bay Area. Workday priced at $28.00 a share last night, above an initial estimated pricing range of $24.00 to $26.00, and had gone as high as $49.00 in morning trading; Workday's venture backers are Greylock Partners and New Enterprise Associates. Workday is trading on the NYSE as WDAY. Bezos is the founder of Amazon.com.