While this pronouncement may be a little early, it looks like Facebook investors are in for a very merry Christmas indeed.  The value of the company’s stock has continued to rise on the private market, and the company’s now supposed to be worth a whopping $50 billion, up from $41 billion earlier this month.

Michael Arrington calculated, "Around $40 million changed hands last week in a Facebook share auction held by SecondMarket.  The end price per share was $20.76, and about 1.9 million shares were bought and sold.  And based on there being around 2.5 billion shares outstanding after a 5-1 stock split earlier this year, that values Facebook at around $50 billion."

Care to do a little comparing and contrasting?  Before the trading day began this morning, AOL had a market cap of just $2.58 billion.  Yahoo had a market cap of $21.35 billion, and eBay had a market cap of $39.41 billion.

Amazon, meanwhile, had a market cap of $80.56 billion, and Google had a market cap of $186.14 billion.  Microsoft had a market cap of $216.54 billion, and Apple had a market cap of $290.67 billion.

So this development doesn’t put Facebook close to the top of the tech pile, financially speaking, but the company’s value is still quite impressive.  Not a lot of young and still-private organizations have managed to leave Yahoo and eBay behind with so little effort.

If Facebook gets more serious about advertising – and/or decides to go public – its value is almost sure to soar some more, as well.