What: Shares of online job search specialist Monster Worldwide (NYSE:MWW) climbed as much as 15% on Thursday after its quarterly results and outlook impressed Wall Street. At 1:30 p.m., the stock was up 9% from the previous close.

So what: Monster shares have been volatile over the past year on uncertainty over the company's turnaround plans, but solid Q2 results -- adjusted EPS of $0.10 on revenue of $180.4 million -- coupled with upbeat guidance reignites optimism over its long-term growth trajectory. While Monster's European business continues to experience strong market headwinds, management's initiatives to cut costs and expand its user-base seem to be taking particularly strong hold in the Careers-North America segment.

Now what: Management now sees full-year adjusted operating EPS of $0.09-$0.13 and expects to exit 2015 with a Q4 EBITDA margin of 18%-22%. "We are increasingly confident that our family of new strategic products are additive to our traditional core products and provide a superior competitive solution for our customers," said President and CEO Tim Yates. "Our focus on sales execution in North America is beginning to prove effective." Given Monster's still-shaky competitive position, hefty debt load, and extremely volatile shares, however, conservative Fools might want to remain on the sidelines.