The strong in Silicon Valley are getting stronger while the weak are looking more sickly amid all the global economic turbulence.

On Tuesday, Apple and Yahoo reported widely diverging earnings to Wall Street. Apple was way up on boffo iPhone sales, while Yahoo, way down on a 64% earnings drop, announced job cuts of at least 10%, or approximately 1,400 employees, by year’s end.

The trims, part of a bid to cut $400 million from the Netco’s budget, are the second major cutback this year: Yahoo cut 1,000 jobs in January, and has struggled to retain key execs as it fended off Microsoft’s unsolicited bid earlier this year — and that was before the economy took a dramatic turn for the worse a month ago.

During Yahoo’s conference call with analysts, topper Jerry Yang repeatedly referred to economic conditions, citing the uncertain advertising market, but also reminded listeners that the company had weathered a down cycle before when the tech bubble burst. However, that was before Google took control of the search ad biz; Yahoo’s recent track record certainly doesn’t inspire confidence, but its rival’s does.

Last week, Google posted strong earnings, albeit showing slightly less growth than it had in the past. Netco’s income jumped 26% jump to $1.35 billion on healthy demand for the search ad biz, while net revenue, excluding commissions, rose 34% to $4.04 billion.

At Yahoo, by comparison, income plunged to $54 million from $151 million during the comparable period a year ago; revenue increased 1% to $1.8 billion.

Yahoo execs said the slowdown hit them in other regions, such as Asia, as the global economy imploded during the quarter. Display ads were especially hard hit. “This is in many ways an unprecedented ad market,” Yang said.

However, the downturn has yet to curb consumers’ appetite for Apple gadgets. The company sold a whopping 6.9 million iPhones in its fiscal fourth quarter, compared with 1.1 million during the comparable period, causing topper Steve Jobs to crow that Apple had sold more smart phones than RIM, maker of BlackBerry.

Apple posted a 26% profit gain to $1.14 billion and a 27% increase in revenue to $7.9 billion during the quarter.

The company said it has yet to see much fallout from the economy. And Apple chief Steve Jobs shrugged off the impact of the slowdown on his high-priced product lines, telling analysts he would be surprised if the downturn sent consumers to lower-priced competish, explaining that Apple was not targeting consumers who shop based on price.

However, Apple execs took a “prudent” approach toward its guidance for the December quarter. “We don’t yet know how this economic downturn will affect Apple,” Jobs conceded. But he maintains that the company is well positioned, noting it has $25 billion in the bank.

Even Yahoo’s Yang insisted he remains encouraged about the outlook for his company. After the call, however, he sent staffers a missive advising them the staff cuts would be coming in a few weeks. The company hopes to shift some jobs overseas to Eastern Europe and Southeast Asia, including India, to further reduce costs.