In a highly anticipated move, Zynga officially filed to go public on Friday.

It's easy to see the appeal of the leader in social gaming. There are 60 million active daily gamers through Zynga's sticky portfolio of casual diversions, logging 2 billion minutes of playtime a day. After posting losses in its first two full years of operation, Zynga broke into the black last year by posting a profit of $27.9 million on $597.5 million in revenue. Zynga's top line more than doubled to $235.4 million during this year's freshman quarter.

We still don't have a price range or even know how many shares will be offered, but media outlets are speculating that Zynga will hit the market at a valuation between $15 billion and $20 billion.

This may seem like a lot of money for a fledgling upstart that didn't even exist until 2007, but one can't underestimate the magnetism of Zynga's games, including FarmVille, CityVille, and Scrabble knockoff Words With Friends.

Zynga's eventual public valuation will turn heads, and it will lead to more speculation about a Web 2.0 bubble that's ripe for bursting.

Just to give fuel to the worrywarts, let's go over five companies that command market caps of less than $15 billion before trading started today.

  • Activision Blizzard (Nasdaq: ATVI) -- $13.6 billion. Yes, the world's largest gaming-software company is worth less than Zynga. An empire fueled by years of Call of Duty juggernauts and World of Warcraft online gamers, and Zynga is ahead of Actvision Blizzard with its virtual farms. Don't even think about Electronic Arts (Nasdaq: ERTS) at $8 billion.
  • Netflix (Nasdaq: NFLX) -- $14.2 billion. Netflix isn't cheap these days, but it's cheaper than Zynga's alleged price tag. Netflix isn't growing as quickly as Zynga, but at least it has years of profitability. Its operating profit last year was also more than twice what Zynga delivered.
  • Mattel (Nasdaq: MAT) -- $9.7 billion, The world's largest toy maker -- and the company with the rights to Scrabble outside North America -- is no Zynga. Sorry, Barbie.
  • Hasbro (Nasdaq: HAS) -- $6.2 billion. The second largest toy company -- and the company behind Scrabble in the United States and Canada -- is worth less than half of Zynga. In fact, if Zynga hits the market at $16 billion, it will be worth more than Mattel and Hasbro combined.
  • LinkedIn (NYSE: LNKD) -- $8.9 billion. Facebook isn't public, but the second most successful social-networking site did go public a few weeks ago. LinkedIn isn't cheap. It's the one name on this list that generated lower revenue and earnings than Zynga last year. However, even Mr. Market's appetite for fast-growing Web 2.0 stocks wasn't enough to push LinkedIn into a valuation in the 11 digits.

Zynga is promising, but it's not going to set the world on fire if it's already commanding a $15 billion to $20 billion market cap out of the gate.

Will you be a buyer or seller of Zynga if it's able to complete its IPO? Share your thoughts in the comments box below.

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Longtime Fool contributor Rick Munarriz remembers when social networks were an offline endeavor. He owns shares of Netflix and is also a member of the Rule Breakers analytical team, seeking out the next great growth stock early in its defiance. The Motley Fool has a disclosure policy.