It's that time of year again—time to step back and try and assess the last 12 months and think ahead to what awaits us in 2010. In that spirit, the final StreetWise column of 2009 takes a look at a baker's dozen of Wall Street (or quasi-Wall Street) figures who represent some important trend or issue during the year. It's not a list of the most influential people on Wall Street, of those with the biggest bonuses or most awe-inspiring titles. Rather, they're involved in something interesting and potentially transformative. Perhaps they are running a new business or tackling a new job. Or they could, like Lloyd Blankfein, simply be trying to return as rapidly as possible to "business as usual." This isn't intended to be a definitive list, but rather a starting point for debate and discussion about the most significant themes of 2009 on Wall Street and what may lie ahead. Happy New Year!

1. Topping our list is none other than Ben Bernanke, the Fed head. But he's not on the list because of his ability to control interest rates and shape monetary policy, or even for his role as ultimate supervisor of financial institutions. He's here because the Fed has become, de facto, the largest hedge fund in the world. Skeptical? Just look at the Fed's own numbers: By the end of the third quarter of 2009, it had purchased $970 billion of troubled assets (the bulk of them mortgage-backed securities) from firms that hit the skids in 2008, such as Bear Stearns, Fannie Mae, and AIG. It plans to keep buying these securities until spring 2010, and Bernanke will end up overseeing a pool of $1.5 trillion in assets. Too bad he'll only collect his $191,300 salary and royalties on his books instead of the typical 2 percent management fee other hedge fund managers can charge.

2. For years, its critics have referred to Goldman Sachs as a hedge fund disguised as an investment bank, pointing to its principal investing and proprietary trading operations. Maybe that's what started Ken Griffin's mind moving in new directions. If a Wall Street investment bank could actually be a hedge fund in disguise, what was to stop a hedge fund from becoming an investment bank without the disguise? In 2009, Griffin recruited some senior bankers to make his vision a reality. True, Rohit d'Souza, his chief architect, decamped in the autumn, but not before he had recruited dozens of bankers and traders to get Citadel Investment Group going. Will companies trust a hedge fund when it comes to doing their trading and banking? Insiders aren't worried; the rest of Wall Street publicly pooh-poohs the plan but privately worry Griffin may be as formidable as an investment banking rival as he has been a hedge fund client.

3. Griffin isn't the only guy outside the investment-banking universe to dream of grabbing market share from Goldman, Morgan Stanley, and the behemoths like Bank of America. It's been a few years since buyout giant KKR hired Citigroup banker Craig Farr to build an in-house investment-banking division to serve the firm's own portfolio companies. For the most part, Farr has focused on doing just that, but KKR's cash infusion into Eastman Kodak a few months back revived speculation that the private equity firm could have bigger and broader ambitions. "Who knows where they could take this?" says one banker. Other buyout managers say it's only logical that their firms could try to supplant the traditional investment banks when it comes to finding capital for companies, even when they aren't portfolio companies. KKR's investment in Eastman Kodak gives the buyout firm two board seats and the possibility of acquiring a 17 percent stake down the road, but as of now, it's not a KKR portfolio company. "It's only a small step from doing this on their own behalf to doing it on a fee basis for a company looking for capital," says a rival buyout manager. "This is going to be interesting to watch.

4. No 2009 list would be complete without including the current King of Wall Street. King Lloyd, that is. Mind you, Lloyd Blankfein may be finding that his crown is getting a bit uncomfortable these days, between proddings by journalist Matt Taibbi and anger about a return to record bonus payments to his firm's employees. Taibbi may have gone down in the business journalism hall of fame as the author of the Rolling Stone article in which he labeled Goldman as "a great vampire squid wrapped around the face of humanity, relentlessly jamming its blood funnel into anything that smells like money." But Blankfein, perhaps rattled by all the negative buzz about the Goldman juggernaut, produced a memorable sound bite of his own later in the year in an interview aimed at burnishing the firm's image. Alas, it proved memorable for the wrong reasons: King Lloyd says that, as a banker, he's just doing "God's work."

5. Was it another bad case of "foot in mouth" disease, or just a bout of honesty? Either way, John Mack, recently resigned as chief of Morgan Stanley, makes our list for declaring outright that regulators need to take a more active role overseeing what Wall Street is up to. "We cannot control ourselves," he admitted to a large audience (including a passel of financial journalists) attending a discussion about coverage of the Wall Street's crisis. Probably most of his listeners already had figured out that was part of the problem, but it was refreshing to hear someone actually admit it. A few more such public acknowledgments might defuse some of the populist outrage.

6. Delivering the increased scrutiny requested by Mack won't be a problem for Elizabeth Warren. The Harvard law professor is on our list not just because she's been heading a Congressional oversight panel monitoring the TARP program, but because her ideas were instrumental in shaping some key elements of the financial regulatory reforms, notably the creation of a Consumer Financial Protection Agency. President Barack Obama wants such a body to have real power to protect Americans from mis-sold products (if not their own eagerness to get deals that are too good to be true). And if the legislation creating it passes the Senate, Warren will be the candidate to beat to head it. That would make her one of Washington's most powerful regulators.