In the next couple of days I hope to update a post I put up a short time ago, one that, as of today, 8/29/11, still holds true. The issue that I addressed in that post was : What does the Large Hadron Collider (LHC) currently have to say about Supersymmetry? I took a slightly polemical point of view, but you can look at the links in the post to longer, more pedagogical articles to see where the point of view comes from.
The problem with trying to answer a question like this one — What do LHC results imply for Theory X — is that it is ill-posed. An experiment searches for a phenomenon — not a theory. If a theory always predicts a certain phenomenon, then an experiment can search for that phenomenon, and, in finding it or not, give a definitive thumbs-up or -down to the theory. But often a theory has many versions, and although it will have a general set of predictions — supersymmetry, for instance, predicts superpartner particles — its details can look quite different to an experiment, depending on the version. [For instance, in supersymmetry, whether or not one sees the classic supersymmetry signature depends on the masses of the superpartner particles, on whether there are extra types of particles that are not required by the theory but might just be there anyway, etc.] So any given experimental result is just one important but incomplete piece of information, one that constrains some versions of the theory but not others. Typically, to entirely rule out a general theory like supersymmetry requires a large number of experimental searches for many different phenomena.
Conversely, though, many different theories may predict the same phenomenon. So an experiment that looks for but fails to find a certain phenomenon doesn’t just rule out just one version of one theory. It typically rules out several versions of many different types of theories.
And if it does find that phenomenon, it does not tell you which of those different types of theories it comes from. Remember that, when the LHC makes its first discovery! You’ll likely see claims from physicists in the press about what the discovery means that aren’t really merited by the data.