Majority Rules

This years election brings a lot of changes to the entire government of the United States, including such places as the Supreme Court. Something that was brought to my attention recently was how the majority rule of the Supreme Court could change.
The Supreme Court is made up of nine members, and currently there are four liberal members, and four conservative members. This, therefore, means that the vote usually depends on one member (Anthony Kennedy), and one vote. Two of the other members of the supreme court are nearing retirement. Justice John Paul Stevens is 88 years old, and no member has ever served over 90.
So, during this term, Justice Stevens (a liberal) may retire. If Obama wins the white house, another liberal justice will be chosen, but if John McCain wins then a conservative justice will be picked. That will switch the majority rule to the conservatives, actually changing many regulations. There could be more gun owners, changes on the abortion debate, and changes on many other issues.
One more point thought, is that people argue that however wins will try and pick someone who will mix things up a little. They may pick someone young, or a female, because there is currently only one woman on the Supreme Court. There has also never been a Hispanic on the Supreme Court, opening that up to possibility also. So whoever wins may be looking for a young Hispanic woman.

What does this mean for our country? If McCain wins, how will the issues change? And what do you thing of a young Hispanic female as a Supreme Court leader, good idea or bad?