shares have been on a tear since announcing earnings on Feb. 25th, up over 10% the day following the release. But what should really have shareholders feeling good is the stock has held onto those gains. That is generally a good sign that there is some substance behind the run-up.

However past, or even current, accomplishments hardly guarantee a sound future. By and large, appears to have its ducks in a row, but as always, there are challenges ahead that if not successfully addressed, could spell trouble. Here are a few key areas investors would be wise to keep tabs on as we move further into 2015.

Monitor global growth
The company has big expansion plans outside of the Americas. Currently, 73% of revenue is derived from the Americas, a bump from 71% in fiscal 2014. In other words, the lack of geographic revenue diversification is getting worse, not better. Of course, that is also an opportunity, one the company is taking aggressive steps to capitalize on.

CEO Marc Benioff made it clear during the earnings conference call that international growth is near the top of the to-do list. And investors should see some results this year. The company is expected to open several new data centers across Europe in 2015, including operations in the United Kingdom, Germany, and France.

How quickly will this European expansion take hold, particularly while butting heads with one of its primary competitors, German-based SAP (NYSE:SAP)? Keep in mind that SAP is not only a CRM competitor. Benioff was gushing over the new analytic cloud tool, which is essentially a comprehensive business intelligence solution. That should sound familiar to SAP fans, as it will compete directly with the SAP HANA analysis tool, which it claims to be the "broadest cloud portfolio and the largest business network in the world." 

It takes money to make money
Not surprisingly, opening data centers across Europe, developing new customer solutions, and ramping up sales in new markets requires spending. is certainly doing that and will continue doing so for the foreseeable future. Last fiscal year alone, total operating expenses jumped 25% year-over-year to $4.23 billion, about $600 million of which was dedicated to sales and marketing.

That kind of spending is necessary to fund the company's significant growth objectives. That said, it is worth watching to determine the impact of higher spending on earnings and whether or not the company is earning a proper return on its multiple investments. Analytic cloud, its improved for small businesses, and international data centers all cost money to develop, but will they pay off? If not, shares could reverse course.

Great expectations
As noted earlier, is firing on all cylinders. If future guidance of another 20%-plus revenue growth for fiscal 2016 is any indication, investors are expecting more of the same. And therein lies another challenge. Based on its stellar results of late, the company has raised the bar going forward.

Outstanding quarterly and annual revenue growth has quickly become an expectation, not a surprise. Investors are giving a pass on spending and the lack of geographic diversification because of raised expectations, meaning that anything less than a home run will hit the stock doubly hard.

Will the international expansion and new product efforts take hold, justifying the increased spending and good graces of Wall Street? Investors would be wise to keep an eye on these strategic areas during the quarterly updates but ultimately focus on the long-term health of the business.