For Yahoo! ( YHOO), it's just like the olden days. Except this time around, there's one less digit in the stock price.Displaying volatility reminiscent of headier times two years past, the Internet bellwether's shares jumped Thursday morning following a nasty slide in the preceding days, as investors weighed the disparate implications of an analyst's upgrade and a major shareholder's selloff. The jumpiness illustrates how Yahoo! continues to enjoy the luxury of being a stock investors care about, in contrast to the vast majority of Internet stocks that, like Yahoo!, are more than 90% off their bull-market peaks. After rising as much as 14% Thursday morning, Yahoo!'s shares were trading at $10.31, up $1.18, or 13%. The likely source of the boost was news that went from worse to bad: Merrill Lynch analyst Justin Baldauf upgraded his rating of the company from sell to neutral. That reassessment was based on valuation alone, writes Baldauf in his Thursday morning note. Yahoo!'s growth outlook continues to be cloudy, says Baldauf, and the stock will likely remain near $10 until investors regain confidence in the online advertising market. And that will take time, says Baldauf, whose firm hasn't done recent banking for Yahoo!. But at Wednesday's closing price of $9.13, says Baldauf, Yahoo!'s $2.1 billion enterprise value -- market cap plus debt, minus cash on hand -- translates into a multiple of 10 times estimated 2003 earnings before interest, taxes, depreciation and amortization -- a common media industry yardstick. That enterprise value multiple is in line with more traditional media names, says Baldauf, starting with AOL Time Warner ( AOL). And it's a discount relative to other large Internet stocks such as Amazon.com ( AMZN) and eBay ( EBAY). One of the reasons Yahoo! ended at $9.13 Wednesday evening was that Japan-based Softbank, Yahoo!'s largest shareholder, was unloading a major block of its shares in the company. After selling about 11 million shares back to Yahoo! for about $9 a share and another 30 million shares in various third-party transactions, Softbank now holds about 7% of Yahoo!'s shares outstanding, down from 16.2% in February. Softbank, a longtime seller of its Yahoo! stake, says it made the sale to help fund its broadband activities in Japan. "We continue to have great confidence in the future strategic direction and the growth prospects for Yahoo!," Softbank says in a Thursday statement. Of course, before investors heard this show of support Thursday, they apparently caught wind of the selling Wednesday; shares dropped $1.57 that day, or nearly 15%, helping create a four-day slide of 29%.