I asked at box office yesterday - and they said they didn't think they're were going to be any concessions.
I have read it somewhere under 16's and OAP are half price but cant remember where, it must hav been on here yesterday. Or on wembley site. but i cannot find it again so maybe not. when all said and done they are taking a seat its like cheaper airoplane seats
From the FA Website There is no mention of any concessions http://www.thefa.com/TheFA/ContactUs/Postings/2008/03/SemiFinalTicketInformation.htm
Last years Blackburn v Chelsea match there were concessions Taken from the Blackburn website http://www.rovers.premiumtv.co.uk/staticFiles/ba/9/0,,10303~68026,00.pdf Concessions The only concessions available are in the £25 price band and are situated in the lower tier of the East Stand. Concessions are £12.50 and are available to Juniors (Under 16) and Seniors (65yrs and over). All children, regardless of age, must have a ticket. Supporters will be required to demonstrate proof of age at the turnstiles. Also the Sunday match was a 4pm kick-off.