Periodic Supreme Court detour...
The idea is that if there's a sudden swing in political opinion (as there has been in the last three years) there is at least one part of government that thinks back longer than the most recent catastrophe.
Whether they are conservative or liberal politically may influence things like whether they actually care to look at the larger history, or the particular circumstances of some cases at all. It's ultimately a matter of interpretation and sense of social timing. You mentioned abortion and sodomy -- at least, some big name cases. If I'm not mistaken, the sodomy case also involved rather brazen invasion of a home. That is something of a conflating issue.
To pick just one counter-example, while the court has allowed Guantanamo prisoners to sue the US, it has refused to take up a torture case "without comment"... Obama's reticence on the subject of Bush administration roundups aside, I don't see this as a case of the court being especially liberal. http://www.huffingtonpost.com/2009/12/14/supreme-court-rejects-gua_n_391176.html
In the end, whether you consider those judges conservative or liberal has a something do with your politics. However, there are also researchers who hold that the Court has been packed with conservatives. For example:http://partners.is.asu.edu/~george/vacancy/justices.html
For the 2006-07 term, 30 cases are identified and Stevens is listed first, having voted in the liberal direction on all but one of those cases. Alito voted in a liberal direction only 2 times, marking him as the most conservative justice for 2006-07, though Thomas, Scalia, and Roberts were right there with three liberal votes out of the 30 cases. The result is an ordering of the justices from most liberal to least liberal (most conservative), Stevens and Ginsburg being the most liberal, with little to distinguish the conservative bloc of four.http://partners.is.asu.edu/~george/vacancy/index.html
This table [ http://partners.is.asu.edu/~george/vacancy/table_guttman_2006.html ] reveals much about the new dominance of the Court by a conservative majority made up Chief Justice Roberts along with Justices Scalia, Thomas, Alito, and Kennedy. For those thirty cases, nearly three-fourth (22) were decided in a direction that could be defined as more conservative than liberal. While somewhat less cohesive than the most conservative bloc of four, Justices Stevens, Ginsburg, Souter, and Breyer hold down a more liberal position on most of these issues and occasionally muster some victories when Justice Kennedy swings over to their position. Exactly two-thirds of these 30 cases were decided by five-to-four votes and Justice Kennedy was on the winning side in all twenty of them. Indeed, Kennedy was on the winning side in 29 of the 30 cases, some 97%. The Chief Justice was the next most winning member with 83%.
Last year's 2007-08 term [ http://partners.is.asu.edu/~george/vacancy/table_guttman_2007.html ] produced modest changes. The Guttman-scaled table of liberal/conservative cases reveals a set of cases almost evenly split in outcome, 14 liberal outcomes and 16 conservative outcomes. This is reflected by Justice Kennedy's score of 50%. One should not interpret these results as reflecting any change in the Court. The conservative group did not somehow become more liberal. These changes reflect the issues brought by the specific set of cases, for the most part providing fewer clear-cut liberal-conservative issues than in 2006-07. Ginsburg remains the most liberal justice, but this time joined by Souter rather than Stevens, who had some interesting alliances with the conservative bloc in Irizarry v. US, Medellin v. Texas, and Crawford v. Marion County Election Board. Thomas came in as the most conservative member of the Court.
Outcomes on the Court will not change much with Sotomayor's replacement of Souter. The most critical appointment this decade was President Bush's replacement of Justice O'Connor with Samuel Alito, a solid conservative supplanting the pivotal Sandra O'Connor, insuring more frequent conservative outcomes in 5-4 decisions. The pivotal position relinquished by O'Connor passed to Anthony Kennedy, who joined the conservative bloc of Roberts, Scalia, Thomas, and Alito more often than not (15 out of 20 occasions in 2006-07 in which a 5-4 vote divided the conservative bloc from the more liberal bloc of Stevens, Ginsburg, Souter, and Breyer. Click on the Justices link if you wish to see voting data from the Court's 2007-08 term.
Following that, there is a claim that Democrats may have an opportunity to recoup influence. However, that scenario requires them to both replace both aging liberal judges and some of the conservative ones. Which brings us back toward the potential impact of the filibuster.
In any case, this contradicts any notion that the Court has become liberal due to Reagan-Bush nominations.
There's no reason that a case has to be heard and decided on in the same term. If lower courts issue so many opinions in violation of precedent that the Supreme Court gets backlogged (which I find hard to believe), then it's the lower court's problem - the Supreme Court can issue certiorari on all of them, and until they decide on the case the lower court's judgment will be suspended.
I suppose they could. If the situation were that messy, however, I suspect we would also be rushing on to threads about whether to shorten the tenure of Supreme Court justices. It's not a formal mechanism, but at some point, if the Court misgauges public opinion or the impact of a specific situation too dramatically... Then more people may demand more accountability from the Court. At the least, there would be an impact on the next set of nomination hearings. It could be more.
Also, not all litigants will have the resources, patience and circumstances to reach the Supreme Court. That is, if they believe their chances are any better with the ideological mix at the top than in federal Circuits. Some hot-button, pressing issues rarely come to the Supreme Court because parties are concerned that the Court might shoot them down and set a "higher" precedent for another generation. (For example, there is some fear that an unsuccessful push on gay marriage now could block anyone else from trying for some years.) So again, if the federal courts are packed, then the real ability of the Supreme Court per se to respond to legislation is rather limited. I still think today, both levels of court are packed in the same direction. It's still a problem, if one relies primarily on the courts for balance.