Here are the top stories about Facebook this week:

1. Mon 22 Oct: Valleywag reports that Facebook has started rolling out its new advertising system that allows advertisers to target demographically as well as by keywords. The new system is rumoured to even deliver exact potential profiles that can be targeted by a given demographic selection.
2. Tue 23 Oct: Google News launch a Facebook app. Google claim the app is well received, but it doesn’t quite cut it, in our eyes. Elsewhere, Jerry Yang, CEO of Yahoo! said that they are not interested in acquiring Facebook. In his words, “Yahoo can’t be Facebook tomorrow, and we don’t want to be Facebook.”
3. Wed 24 Oct: Wall Street Journal reports that Microsoft has acquired an equity stake of 1.6 per cent of Facebook for $240 Million, valuing the company at $15 Billion, which is 500 times its estimated 2007 earnings of $30 million.
4. Thu 25 Oct: Reuters reports that Facebook is seeking to raise another $260 million in financing from hedge funds and private equity investors, in addition to the funding received from Microsoft. The Wall Street Journal says that an announcement of further funding is just days away.
5. Fri 26 Oct: Financial Times reports further that Facebook is looking for additional investment in order to hire 400 new staff, buy more computers and invest in building a new advertising system.

The recent investments make Facebook the highest valuation of any private equity deal ever. Social networking has its detractors. But at present there’s little Facebook could do wrong. Some have even gone so far as to wonder whether social network marketing could be the next SEO.