Facebook priced its initial public offering at $38 per share, which is at the high end of the range it proposed on Tuesday. The price will raise $16 billion for the company and the social network a valuation over $100 billion.

The company plans to list 421.2 million shares of its common stock on the Nasdaq on Friday under the symbol FB. Facebook is offering 180 million of its shares. The remainder of the shares come from existing stockholders — a number of whom decided Wednesday to sell a greater proportion of their shares. Additionally, underwriters have the option to purchase up to 63.18 million additional shares of Class A common stock to cover over-allotments, which they are expected to sell based on demand seen during Facebook’s roadshow.

The IPO will be largest ever for a technology company and the third largest overall in the U.S., behind Visa and General Motors.

Read the rest on our sister site, Inside Facebook.

Mobile ad company Millennial Media shares lost some of yesterday’s blockbuster momentum, dropping 8.2 percent to $22.90 in early trading this morning.

The company’s shares, which trade under the MM symbol on the New York Stock Exchange, debuted on the market yesterday at $13. However, the first trade of the day popped their value to $25. Millennial shares finished yesterday at $25, but fell below $23 before 10:30 a.m. EST.

The company’s market cap is currently $1.73 billion. From its initial public offering, Millennial earned $132 million selling 10.2 million shares at $13 each.

After the IPO, Millennial is now the largest independent mobile ad network. The company’s early competitors like AdMob, Quattro, Greystripe and ValueClick followed the acquisition route, selling to larger companies like Apple and Google. Millennial’s competitors now include startups like InMobi, which is backed with more than $200 million in funding from Softbank, and non-traditional advertising services like MoPub and Chartboost which focus on auctioning or trading inventory rather than directly selling ads.

According to the most recent amendment to its S-1 filing, the ad network reaches 300 million users. It saw a net loss of $287,000 on $103.6 million in revenue in last year.

Before going public, Millennial raised over $64 million in funding from Bessemer Venture Partners, Charles River Ventures, Columbia Capital and New Enterprise Associates.

A game from Zynga called ZombieSmash popped up on our radar this evening.

Curiously, its owner used to be named GameDoctors, an independent studio from Bielefeld, Germany founded by two brothers three years ago. But the owner’s name just changed to Zynga, even though the app has been out for nearly two years. Zynga has not immediately replied to requests for comment.

It may be a sign that Zynga acquired GameDoctors or a sign that the company is starting to publish third-party iOS games. In the prospectus last month for Zynga’s initial public offering, the company said it acquired two companies between the end of the third quarter and Dec. 15 for an aggregate purchase price of $4.9 million. The most likely explanation we’re hearing about from multiple sources — though not confirmed yet — is that this is one of them.

Alternately, Zynga has made number of hires suggesting a move toward publishing. It recently poached Sony’s Rob Dyer, who now heads partner publishing. In September, it also hired Disney game publishing exec Adam Sussman, who used to work at EA Mobile.

Publishing could help defray the risks of being a hits-driven business and help the company cultivate relationships with independent studios it may one day eventually want to acquire. It would also put it in competition with EA’s Chillingo label and with other dual game developers and publishers like 6Waves-LOLApps.

Millennial Media — one of the last large, independent mobile ad networks standing – filed for an initial public offering today.

The Baltimore, Maryland-based company lost $417,000 on $69.1 million in revenue for the first nine months of this year. That’s down from a $5.4 million net loss on $29.1 million in revenue in the same time a year before. While pricing stock option grants in June, Millennial valued itself at $305.3 million in June based on a multiple of 2.5 on 12 months of trailing revenue.

Millennial is going out to market after a wave of consolidation over the last two years. Its most formidable competitors, AdMob and Quattro, were bought by Google and Apple while smaller networks like Greystripe went to ValueClick and Mobclix went to Velti.

Google and Apple’s ad networks probably remain the company’s biggest rivals given that both operate the leading smartphone platforms, have far more capital at their disposal and strong relationships with both device makers and carrier partners. InMobi has also picked up momentum over the past two years and raised $200 million in funding from Softbank in September. Then there is a crop of young startups like Mopub and Chartboost which help developers mediate between lots of different mobile ad networks, sell their own inventory and broker direct advertising trades with other developers.

Millennial argues that it’s well-positioned however, after serving 40 billion impressions to 200 million unique users globally in December. The company says that its technology platform has precise targeting capabilities based on the device, operating system and strength of its data connection to serve ads. It also says it has data on 150 million unique users, allowing behavioral or personal targeting.

The company has raised more than $64 million in venture funding from Bessemer Venture Partners, Charles River Ventures, Columbia Capital and New Enterprise Associates. Its last round added no new venture investors.