The micro-blogging website Twitter is ending the year with a new round of funding, having raised $200m against a valuation of $3.7 billion. According to All Things Digital, the funding included the addition of 2 new board members and is a significant development for Twitter as it continues to upgrade its management and business model.

This new input of funding will help support Twitter's expansion plans and also indicates to bigger companies (such as Google) that it's not for sale!

In another article from Paid Content, which also reports on the Twitter funding, there is a summary of the main venture capital funding for online companies in 2010, including Yelp, LivingSocial and Groupon (which recently rejected a takeover bid from Google).