Shares of Finnish telephony legend Nokia (NYSE:NOK) surged more than 23% this morning. The stock is trading at prices not seen since last April, when the then-fresh Lumia 900 smartphone series still seemed like a threat to the established wireless world order.

Nokia plunged over the summer as low-cost Android phones basically destroyed the Lumia's target market. But who cares about summertime sales, when smartphones typically thrive during the holidays? Today's spring-loaded bounce is a market reaction to Nokia finally getting some traction, just in time to greet Christmas shoppers.

NOK Chart

NOK data by YCharts.

The company announced some preliminary holiday-quarter results, and it was generally good news. In particular, Lumia sales of 4.4 million units were "better than expected," in Nokia's own words. Both the handset division and the Nokia Siemens (OTC:SIEGY) infrastructure equipment venture will deliver positive operating margins this time. The handset operation clears the break-even point by the slimmest of margins, but that's still better than the 6% negative margin management had predicted.

Still, I think it's a little early to proclaim Nokia's triumphant return to a leadership position. Four million flagship phones sounds like a lot, but that's a worldwide number for the seasonally strong holiday quarter. By comparison, Apple (NASDAQ:AAPL) sold 10 million iPhones through AT&T (NYSE:T) alone, and Google (NASDAQ:GOOGL) activates more than 1.3 million new Android devices every day. There's a lot of heavy lifting left to do, and I'm not at all convinced that Nokia has the muscle to pull it off.

That's why I'm not telling you to back up the truck here. In fact, if you bought Nokia shares at rock-bottom prices in recent months, this looks like a reasonable time to take profit off the table. Share prices have nearly tripled from 52-week lows, after all. Nokia remains a speculative bet at best, even with one not-too-terrible quarter under its belt.