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News Summary: LinkedIn posts solid 4Q, doubts loom

The Associated Press

GOOD JOB: LinkedIn's fourth-quarter earnings and revenue exceeded analysts' projections as the online professional networking service added another 18 million users during the final three months of the last year. The gains left LinkedIn with 277 million people who have listed their job histories on the site, making it an increasingly valuable tool for employers.

POTENTIAL TROUBLE AHEAD: The results announced Thursday were overshadowed by a management forecast indicating that LinkedIn Corp's performance may falter this year amid increasing spending on long-term projects and slowing revenue growth.

UNHAPPY INVESTORS: LinkedIn's stock fell by 8 percent in Thursday's extended trading.