FINAL UPDATE: Facebook's stock went on a wild ride today, its first day of trading.

The closing price is $38.23.

It all started around 11:45 this morning, when after a long delay Facebook opened for trading at $42.05.

It rose to $43 before ultimately collapsing back to $38.

The bankers underwriting Facebook's IPO priced it at $38, so there was zero stock "pop."

This is bad news for people that wanted to buy the stock and flip it for a quick profit.

It's great news for Facebook because it means its bankers priced the IPO perfectly. In fact, they may have done better than price it perfectly. They may have gotten Facebook a great deal.

The stock was crashing throughout the day and it looked destined to fall below $38. However, the underwriters were hammering the stock with buy orders to prevent it from dropping below $38.

It worked, and now the stock is sitting just over $38.

What happens next week? We'll find out ...

Below is our coverage of the stock's movements throughout the day.

UPDATE #2: Facebook tanked to end the day, falling to $38.00.

It's been fighting to stay above $38 for the last few minutes of the trading day.

We still have some trading time left for it to swing either way, so stay tuned...

The reason it's not cracking $38 is because Facebook's army of underwriters won't let it crack. They're putting in orders to make sure it doesn't drop.

UPDATE: Facebook opened at $42.05, but fell back to the IPO price of $38.

The stock has climbed back and it's now at $41 as of 12:35 PM east coast time.

Apparently there was a problem with the NASDAQ and traders didn't know if the trades were going through. This hurt the stock.

We'll be on it all day, so stay tuned!

Original: Facebook opened at $42.05 and shot up to $43 immediately.

It has since dropped down to around $40 giving it a valuation of ~$110 billion.

The stock was priced at $38 for the IPO, so it's up just 5%.

This is quite unexpected. Most people were assuming the stock would have a monster pop at the opening.

We'll be monitoring the stock all day long, so stay tuned!

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