It's been a mixed bag for IPOs this week. But, as for the MercadoLibre (NASDAQ: MELI)'s offering, things were certainly upbeat.

The IPO priced at $18 (at the top of the $16-$18 range) and raised a cool $332.8 million. So far, shares are trading up 38% to $25.

MercadoLibre operates the largest online trading platform in Latin America (which has about 550 million or so people). In fact, the region is experiencing high rates of internet penetration.

MercadoLibre has an assortment of services: product listings, which are based on either a fixed-price or auction-based format; classifieds; and secure payment solutions. There are more than 2,000 product categories, and the sites attract about 2.9 million listings per month.

The top-line growth has been impressive. From 2004 to 2006, revenues surged from $12.7 million to $52.1 million. During this time, operating expenses increased at a slower rate, going from $16 million to $46.7 million. In other words, the company is realizing operating leverage.

There is competition, such as from DeRemate and MasOportunidades.com. There is also pressure from large online communities like Google (NASDAQ: GOOG), Amazon.com (NASDAQ: AMZN), Microsoft (NASDAQ: MSFT), and Yahoo (NASDAQ: YHOO).

Also, eBay (NASDAQ: EBAY) owns roughly 19% of MercadoLibre. However, the strategic alliance has expired and eBay is now able to become a competitor as well.

The lead underwriters on the deal include J.P. Morgan Securities Inc. (NYSE: JPM) and Merrill Lynch (NYSE: MER).

You can find the prospectus at the SEC website. Also, if you want to check out more IPO pricings, click here.

Tom Taulli is the author of various books, including the Complete M&A Handbook and the EDGAR-Online Guide to Decoding Financial Statements.

Last December, over 100 stocks were featured in our Top Picks for 2007 report. Now, at mid-year, we turn to the 20 advisors whose picks showed the strongest gains to get an update on their previous picks, as well as a new favorite stock for the second half of the year.

John Christy, editor of the Forbes International Investment Report, chose Nokia Corp. (NYSE: NOK) as his favorite stock for 2007, which rose 39% as of 6/1/07. Here is his original recommendation for Nokia and his current opinion on the stock.

For his new favorite stock, the advisor looks south of the border, recommending América Móvil (NYSE: AMX). He explains, "Latin America has been one of the hottest regions for global investors in 2007. As of May 25, the Morgan Stanley Capital International Latin America index is up over 17% in U.S. dollar terms.

"But there's still plenty of money to be made south of the border. AMX is the dominant mobile phone service provider in Mexico. The company's reach extends beyond its home market to more than 125 million subscribers throughout Latin America, with operations in more than a dozen countries.

"Revenue topped $21 billion last year, about half of which came from outside Mexico. The company is controlled by Carlos Slim Helú, who overtook Warren Buffett earlier this year as the world's second-richest man.