Fermilab's talking head, Don Lincoln, has recorded numerous videos on cool physical topics so it shouldn't be surprising that he has added the coolest topic of all as well, superstrings.
This 8-minute video begins with the classification of elementary particles in the Standard Model, says that the list of ingredients is messy, and argues that there should be a simpler picture. Superstrings represent particles of different species as different "Chladni patterns" of white powder on a speaker. He mentions that the real superstrings vibrate in 11 spacetime dimensions – well, there are no 1-dimensional strings in 11 dimensions (in M-theory) but I don't want to be picky here. ;-)
Lincoln says that the theory is totally "cool" but you should "not believe it" because there is "zero evidence".
I understand the sociological perspective from which these proclamations are fair and balanced. After all, many string theorists like to say the same thing. On the other hand, I still do find this fair and balanced picture irrational.
A rational person believes something if the probability that it is valid obtained by rational arguments is greater than (or much greater than) 50 percent. In science, the rational arguments always rely on some empirical input at the end. But the way how the empirical input is used to decide about the fate of theories is always indirect to some extent – it is either slightly indirect or very indirect, the arguments rely on lots of complicated gadgets and/or lots of mathematics or a small amount of those intermediate agents.
When it comes to these epistemic principles, string theory doesn't differ in any qualitative way from quantum field theory – or from simpler theories, for that matter. So saying that one "should not believe" string theory is about as reasonable or, more realistically, as unreasonable as saying that one "should not believe" quantum field theory or general relativity.
They're just two frameworks that boast the explanatory power to explain all the observations we have ever made. They are really competitors of one another. Quantum field theory uses a language that is closer to what we immediately observe. After all, effective quantum field theory is directly constructed to contain all the relevant objects and processes at a given length scale.
But the fundamental theory of the Universe doesn't have any reason to use a language that is close to some mundane scale of 21st century experiments. Another advantage of quantum field theory is that we know rather clearly how we should adjust its list of fields, particles, and interactions to yield a model (the Standard Model) that immediately describes the observations; in string theory, we have many rather different compactifications to produce a realistic vacuum.
Nevertheless, when we compare the two competitors according to any other feature, string theory has a smaller or larger edge in comparison with quantum field theory.