Earth2Tech takes a look at a report from The Cleantech Network that paints a rosy picture for green tech enthusiasts. It turns out that 2006 was the year when the tide turned to the tune of $3.9 billion in investments.

It was a “watershed period” in the industry, according to the group, as investment in the sector rose 70 percent in 2006 and the market began to see its first successful cleantech IPOs and M&As. Venture investors put $3.9 billion into cleantech companies in North America, Europe and Israel — $1.6 billion more than in 2005.

Click for a concise, bulleted list of some of the pertinent data.

How will 2007 turn out?