Shares of Bank of America (BAC 3.35%) are up more than 2.5% in intraday trading on Tuesday following Warren Buffett's positive comments about the bank's CEO, Brian Moynihan, coupled with another analyst upgrade.

The question of whether to allow Moynihan to continue occupying the chairman and CEO roles is the biggest issue facing Bank of America right now. The roles were combined until shareholders voted in 2009 to separate them following the bank's near-death experience the previous year.

The problem is that Bank of America's board recombined the roles in 2014 without shareholder approval. "There's more work ahead, but Brian's strategy to simplify the company and connect it with the real economy continues to build value for shareholders," former chairman Chad Holliday said at the time. "The board strongly supports the strategy that Brian has set and, after careful deliberation, has decided to take these next steps in our governance responsibilities."

Shareholders weren't pleased. Multiple institutional investors as well as shareholder advisory firms have since opposed the move and are urging shareholders to re-separate the roles in a Sept. 22 vote on the issue. Importantly, aside from high-profile bank analyst Mike Mayo, most of the criticism has been leveled against Bank of America's board, not Moynihan, who most people agree has done a commendable job leading the nation's second biggest bank through the darkest five years in its history.

The good news for Moynihan is that he has Warren Buffett in his corner. "If I could vote, I would vote as management suggests, which is to have Brian take on the CEO and chairman job," Buffett told CNBC on Tuesday. "He's done a first-class job" turning the bank around, the Oracle of Omaha continued.

Although Buffett's firm Berkshire Hathaway has a roughly $12 billion position in the bank, he doesn't have a formal say on the matter. This is because his position consists of preferred stock and warrants to purchase common stock. In order to vote, he would need to own common stock outright. That aside, the mere fact that Buffett is entering the fray speaks volumes. He's the greatest bank investor living and he's long been considered a sage when it comes to proper management and the maximization of shareholder returns.

For its part, Bank of America has couched the issue in terms of flexibility:

The board believes that having the same flexibility on board leadership that 97% of the S&P 500 now have, while still providing strong independent oversight, is in the best interest of stockholders. No company has dug out of a deeper hole since the financial crisis, turned back to health with solid earnings, and has accumulated record levels of capital and liquidity -- also to the benefit of our shareholders. The board respectfully recognizes that stockholders hold varying views on this matter, which is why the board committed to putting it to a vote.

It's impossible to predict if Bank of America's board will prevail. One glimmer of hope is that the same group of institutional investors and shareholder advisory firms lined up against JPMorgan Chase's Jamie Dimon last year for the same reason, yet shareholders in that case voted overwhelmingly in favor of maintaining the combined roles.

The second piece of good news that seems to be fueling Bank of America's stock today is yet another analyst upgrade. Nomura raised its rating on the Charlotte, North Carolina-based bank's stock to a "buy" from a "neutral" and placed an $18 price tag on its stock. This follows similar upgrades by Morgan Stanley, KBW, and Baird, among others.

Generally speaking, now is a great time to buy bank stocks. While valuations at many banks have recovered from the financial crisis, low interest rates are still weighing on the bank industry's profitability. Once this changes, there's every reason to believe that valuations will head even higher on account of the added income.