They Encourage Partisanship. The Post's Ezra Klein tackled the conventional wisdom on the filibuster, that it fosters Congressional bipartisanship "because it forces the majority to cut deals with the minority." Klein argued that "eliminating the filibuster would make the Senate a more, rather than less, bipartisan institution" because of the incentives it sets up for members of the minority party:
A minority legislator's first goal is to win reelection. Their second goal is to reenter the majority so they can write the legislation. Giving the ruling party a major accomplishment -- either bipartisan or partisan -- makes both goals harder to achieve. So the minority does not use the filibuster for that purpose. The goal is not a bipartisan bill. It's no bill.
Maybe Unconstitutional? Kevin Drum of Mother Jones agreed, citing Congressional budget resolutions, where filibusters are forbidden and which Drum says are more bipartisan. Drum also argued that the Supreme Court should strike down filibusters as against the spirit of the Constitution. "The fact that certain types of legislation (treaties, constitutional amendments, veto overrides, etc.) specifically require supermajority votes is evidence that the framers assumed that ordinary legislation should be passed by majority vote," he wrote.
Constitutional or Not, They're Here to Stay. Matthew Yglesias brought the wonk by noting that the Supreme Court can't intervene against filibusters because "The Senate itself is the only adjudicator of its own procedures." Yglesias explained why, even if it might be in the interest of Democrats at large to ban filibusters, it is not in the interest of the individual Senators who make up the Democratic Party. "Even though the filibuster is against the transient interests of the current majority it serves the individual interests of each senator by increasing the worth of his vote," he wrote.