A four-year old company, named after its founder's dog, exploded on the scene today and is instantly as valuable as aging industrial stalwarts such as Alcoa (AA), and competitors Activision Blizzard (ATVI) and Electronic Arts (ERTS). Of course I am talking about the Zynga (ZNGA) IPO, which sold 11% of itself to the public via a 100 million share offering priced at $10 a piece. While that marks the upper end of the company's expected $8.50 - $10 range, it may have also taken most of the 'pop' out of the aftermarket, where the shares unexpectedly fell beneath that level within minutes of opening for trade.

While surprising to some, the stumbling debut shows investors are considerably less thrilled with social media today than they've been over the last few months that has seen huge debuts from LinkedIn (LNKD), Pandora (P) and Groupon (GRPN). It could also set off an exercise of revaluing Facebook, which is set to go public itself next year.

That said, if you are a Zynga shareholder or are considering becoming one, you must understand exactly what are you buying.

The typical accolades note Zynga being the world's largest social game developer and that it "does business" so to speak with 227 million people a month across the globe. It's also a company on track to do over a billion dollars in revenue this year; 90% of which came through its hugely popular Farmville, Cityville, and Mafia Wars games on Facebook.

It is also worth noting that if you end up chasing Zynga in the aftermarket, you will be going against my co-host Jeff Macke's explicit advice.

"DO NOT BUY THIS STOCK," he flatly declares in the attached video clip, echoing the bearish sentiment outlined earlier this week by an analyst slapping a "sell" rating on Zynga before its debut. Arvind Bhatia of Sterne Agee initiated coverage at "underperform" with a $7 a share price target, before the deal had even priced yet - an unheard of move on Wall Street.

Bhatia cites the very same concerns about waning growth, new products and over-reliance on Facebook, as well as the low barrier to entry there is for new competitors to pop up, much the same as the proverbial row of corn you may have invested in.

Zynga says it will use the IPO proceeds to develop and market new games, while pointing to the rapidly growing popularity of its "Words With Friends" application that is available on and off Facebook and can claim Alec Baldwin as its best known player.

If Zynga can continue to deliver triple-digit sales growth and show steady improvement to its small operating profit, then the stock is a steal. If it can't, or its notoriously candid billionaire CEO Mark Pincus serves up a gaffe, then this richly valued growth stock could be in for a similarly rough ride following a splashy debuts of its social media predecessors LinkedIn, Groupon, and Pandora.

Is Zynga a buy or a sell? Let us what you think in the comment section below or visit us on Facebook.