Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Vipshop Holdings (VIPS -1.38%) soared a whopping 30% today after the Chinese online retailer's quarterly results and outlook topped Wall Street expectations.

So what: The stock has soared over the past year on a string of better than expected results, and today's fourth-quarter numbers -- adjusted earnings per share of $0.49 (vs. the consensus of $0.41) on a revenue surge of 117% -- coupled with upbeat guidance suggest that growth is only accelerating. In fact, active customers during the quarter spiked 120% while gross margin expanded 160 basis points, giving analysts plenty of good vibes over Vipshop's competitive position.

Now what: Management now sees first-quarter revenue of $640 million-$650 million, well ahead of Wall Street's view of $578 million. "Heading into 2014, as our recent initiatives suggest, we are committed to further scaling our platform by improving our brand reputation, broadening our product offering, and enlarging our warehousing and logistics capabilities," said CFO Donghao Yang. "We also plan to continue to invest in strengthening our mobile and IT capabilities, in order to more optimally position ourselves to capitalize on the opportunities in China's dynamic, evolving eCommerce market." Of course, with the stock now up a staggering 680% over its 52-week lows and trading at a forward P/E of 50, I'd wait for some of the excitement to fade before buying into those prospects.