I both agree and dissagree.
On one hand is does exist, in varying degrees of severity. I have very mild dyslexia, which mainly affects my reading. I have to read every word on a page or it comes out as completle tosh where as most people can skim read a lot faster.
On the other hand, its become the "thing" to have, and is probably in a lot of cases being used as a one size fits all excuse for crap teaching - "couldnt possibly be us, he/she must be thick/dyslexic/unteachable"
However, my first primary school as appauling and said "he's simply thick, he will never get into Dauntseys (local secondary school)" (direct quote from head teacher to my parents) I swiftly left said school and moved to a decent one, whos teaching levels were far far better and suddely i started learning and achieving. It was them who discovered i had mild dyxlexia, and gave me extra lessons once a week to combat it. I passed the exam to Dauntseys, went to Uni and now lead a happy supra fulfilled life. I really must go back and do a Nelson Muntz style HAAAAA HAAAA at my old head teacher
So i think its a mixed bag, it does exist but is an all too easy label to apply. If your a parent with a child whos struggling - try and get someone who knows what they are talking about to spend some time with them.