Great question -- and one of the biggest problems that parents and researchers face.
The question of diagnosis -- what is Autism or what is an Autism Spectrum Disorder ? To what degree ? What is an appropriate intervention ? How much funding ?
There are a number of criteria that have been used to diagnose Autism over the years, the most common of which I believe is still the DSM-IV definition (under which my youngest wouldn't be diagnosed as having Autism). Without doubt, the change of criteria over the past several decades has contributed to what has been labelled as an "epidemic" (along with general awareness of Autism). Is that the only reason ? I don't know -- both DSM-IV and IDEA (US legislation for education for kids with disabilities) are cited as reasons for the increase in reported cases, but both happened a decade and a half ago and IDEA applies only in the US.
One problem that I have faced is receiving reports from leading professionals who say that my child has an Autism Spectrum Disorder, then being rejected from receiving funding because my child doesn't meet the DSM-IV criteria for Autism, only for Pervasive Development Disorder - No Obvious Cause.
So, to answer your question, nope
We can't even find common ground as to the definition of what constitutes Autism or an Autism Spectrum Disorder or NeuroDiversity (tm?) or whatever, let alone classify how the affected children fall along that spectrum. That will continue to be the biggest hurdle in terms of getting an accurate portrayal of Autism in the media and the reason why that majority of folks like me think that people like Jenny McCarthy are half-informed, very fortunate half-wits who are not helping the majority of kids with Autism.
I definitely don't begrudge her the success that she has enjoyed wrt her son, but her blind arrogance and willingness to shoot her mouth off is harmful. My son saw benefit from the removal of casein from his diet (while my daughter didn't), but he certainly isn't "cured". I personally know families (we attended the conference with two of them) who have done everything that Jenny has done, and FAR more, and their kids haven't improved. If we still can't define the condition, there is no possible way that anybody can claim that it can be cured and anybody who does, should be regarded with skepticism ... but also with hope, because sometimes things DO work for your kid, even if they don't work for everybody.
In terms of specifics, the still-pending DSM-V is looking to redefine the classification and diagnoses, although the direction that they will take is still not known (to me anyway). As an example, Rett's Syndrome, which has previously been classified as a form of Autism (or, more properly, a Pervasive Developmental Disorder) affecting girls, has now been identified as a specific genetic disorder and may be removed from the Autism/PDD classification, although similar things may be said about FragileX (my daughter is neither Rett's nor FragileX, although my wife is a FragileX carrier). It will be interesting to see what happens to eligibility of kids for programs/interventions based on those changes.
All told, this quagmire is a key reason why parents are the best advocates -- they know their children best and, while overwhelmed, emotional and not fully understanding what the hell is going on, are the best positioned to determine the appropriateness of various programs and interventions.
The story of Lil' Nintendoh, and his parents' awareness as to what his needs are, is a good illustration of this.