wait we still have a bush court? I thought when obama got elected he got to instate new judges to the supreme court. If he didn't then how long do we have to deal with the bush court?
A sitting president may nominate any person of their choice to fill a vacancy on the Supreme Court (or, in much rarer circumstances, may ask the Congress to alter the number of seats upon the Court, and if they legislate such an alteration, then he may nominate whom he pleases to fill the resultant vacancies).
Once the nominee has been confirmed into their position by the Senate (as the Constitution mandates that such nominations meet with the approval of the Senate), they occupy their seat upon the Court for life, or until they resign, or unless they are impeached by the Congress for crimes (this has, I believe, only happened once in American history). Otherwise, Supreme Court justices have no term limits.
if the federal supreme court were to uphold judge walker's ruling, would that have any legal impact on gay marriage elsewhere in the united states and if so what impact would it have?
Well, I am no jurist-- only a fancier of the law-- so I cannot say precisely what all the ramifications would be. But if I understand correctly, the issues at hand would be twofold: Prop 8 was an amendment to the Constitution of the State of California. Judge Walker has determined that the amendment must be struck down, because it represents principles in violation of the Federal Constitution. However, the 1996 Defense of Marriage Act passed by the 104th Congress denies the right of marriage to same sex couples at the Federal level. Unless the Court could be convinced that as it stands, there is some implicit right in the Federal government for citizens to marry, and that such a right may not be limited by the Congress to only some citizens (heterosexuals), the Court would likely reverse Judge Walker, and reinstate Prop 8, as it cannot be argued that an amendment in harmony with Federal legislation can be unconstitutional, unless the Federal legislation is also unconstitutional.
If the Court were to decide to do so, they could strike down the Federal Defense of Marriage Act also, thus completely validating the overturn of Prop 8, and also in the process opening the door for invalidating every other State's laws against same-sex marriage. Such legislation might be struck down all across the nation.
Such a decision might not come from any particular support of gay marriage, but from an argument that the Congress has no authority to legislate marriage at the Federal level. There is nothing in the Constitution that specifically gives the Congress authority to make laws about marriage, and authorities not given to Congress are deemed to be the province of the State governments. One might argue that the DOMA is an infringement by the Congress on the civil jurisdictions of the governments of the several States. If the Court is even slightly likely to support the overturn of Prop 8, it will probably be for this reason.
Ironically, while that might invalidate the DOMA and strike down Prop 8, it could also lead to opening doors for suggesting that many other Federal laws are unconstitutional because of infringement upon "States rights." Many civil rights, labor rights, and social protection laws could become intensely vulnerable to overturn. And it would be a shocking precedent. While the immediate goals of affirming the overturn of Prop 8 and perhaps the overturn of the DOMA also are laudable and positive, the Federal government has strongly asserted its dominance over the State governments for a long time, and "States rights" arguments have a long history of abuse. "States rights" arguments precipitated the Civil War, and were used to justify Jim Crow laws, and various other forms of oppression.
What it would mean in the long run for the US in its entirety if the Supreme Court affirms the overturn of Prop 8 is unclear.